Modify casing of marked letters
15
$begingroup$
Trying to learn coding in my 30s.
Could anybody review my code and give me some feedback if possible? It works, but I am sure there are better ways to solve this problem.
The problem:
A text is given. Write a program that modifies the casing of letters to uppercase at all places in the text surrounded by <upcase> and </upcase> tags. Tags cannot be nested.
Here is what I've come up with:
namespace Task6Casing
{
class Program
{
static void Main(string args)
{
Console.Write("Text: ");
string text = Console.ReadLine();
char textNew = new char[text.Length];
int i = 0, j = 0, k = 0;
while (i < text.Length)
{
if (text.IndexOf("<upcase>", k) < 0) // check if there is any <upcase> tag
{ // if no, copy everyting
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < text.IndexOf("<upcase>", k)) // if there is an <upcase> tag, copy letters until the tag
{
textNew[j++] = text[i++];
}
i += 8; // move index i to the position right next to the <upcase> tag
k = i;
}
if (text.IndexOf("</upcase>", k) < 0) // check if there is any </upcase> tag
{ // if no, copy everyting in CAPITAL letters
while (i < text.Length)
{
textNew[j++] = Char.ToUpper(text[i++]);
}
}
else
{
while (i < text.IndexOf("</upcase>", k)) // if there is an </upcase> tag, copy letters in CAP letters until the tag
{
textNew[j++] = Char.ToUpper(text[i++]);
}
i += 9; // move index i to the position right next to the </upcase> tag
}
}
foreach(char c in textNew)
{
Console.Write(c);
}
Console.WriteLine();
}
}
}
c# beginner strings console
edited 2 days ago
Sᴀᴍ Onᴇᴌᴀ
9,95662166
asked 2 days ago
FreddyFreddy
762
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15
$begingroup$
Trying to learn coding in my 30s.
Could anybody review my code and give me some feedback if possible? It works, but I am sure there are better ways to solve this problem.
The problem:
A text is given. Write a program that modifies the casing of letters to uppercase at all places in the text surrounded by <upcase> and </upcase> tags. Tags cannot be nested.
Here is what I've come up with:
namespace Task6Casing
{
class Program
{
static void Main(string args)
{
Console.Write("Text: ");
string text = Console.ReadLine();
char textNew = new char[text.Length];
int i = 0, j = 0, k = 0;
while (i < text.Length)
{
if (text.IndexOf("<upcase>", k) < 0) // check if there is any <upcase> tag
{ // if no, copy everyting
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < text.IndexOf("<upcase>", k)) // if there is an <upcase> tag, copy letters until the tag
{
textNew[j++] = text[i++];
}
i += 8; // move index i to the position right next to the <upcase> tag
k = i;
}
if (text.IndexOf("</upcase>", k) < 0) // check if there is any </upcase> tag
{ // if no, copy everyting in CAPITAL letters
while (i < text.Length)
{
textNew[j++] = Char.ToUpper(text[i++]);
}
}
else
{
while (i < text.IndexOf("</upcase>", k)) // if there is an </upcase> tag, copy letters in CAP letters until the tag
{
textNew[j++] = Char.ToUpper(text[i++]);
}
i += 9; // move index i to the position right next to the </upcase> tag
}
}
foreach(char c in textNew)
{
Console.Write(c);
}
Console.WriteLine();
}
}
}
c# beginner strings console
edited 2 days ago
Sᴀᴍ Onᴇᴌᴀ
9,95662166
asked 2 days ago
FreddyFreddy
762
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15
15
15
2
$begingroup$
Trying to learn coding in my 30s.
Could anybody review my code and give me some feedback if possible? It works, but I am sure there are better ways to solve this problem.
The problem:
A text is given. Write a program that modifies the casing of letters to uppercase at all places in the text surrounded by <upcase> and </upcase> tags. Tags cannot be nested.
Here is what I've come up with:
namespace Task6Casing
{
class Program
{
static void Main(string args)
{
Console.Write("Text: ");
string text = Console.ReadLine();
char textNew = new char[text.Length];
int i = 0, j = 0, k = 0;
while (i < text.Length)
{
if (text.IndexOf("<upcase>", k) < 0) // check if there is any <upcase> tag
{ // if no, copy everyting
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < text.IndexOf("<upcase>", k)) // if there is an <upcase> tag, copy letters until the tag
{
textNew[j++] = text[i++];
}
i += 8; // move index i to the position right next to the <upcase> tag
k = i;
}
if (text.IndexOf("</upcase>", k) < 0) // check if there is any </upcase> tag
{ // if no, copy everyting in CAPITAL letters
while (i < text.Length)
{
textNew[j++] = Char.ToUpper(text[i++]);
}
}
else
{
while (i < text.IndexOf("</upcase>", k)) // if there is an </upcase> tag, copy letters in CAP letters until the tag
{
textNew[j++] = Char.ToUpper(text[i++]);
}
i += 9; // move index i to the position right next to the </upcase> tag
}
}
foreach(char c in textNew)
{
Console.Write(c);
}
Console.WriteLine();
}
}
}
c# beginner strings console
edited 2 days ago
Sᴀᴍ Onᴇᴌᴀ
9,95662166
asked 2 days ago
FreddyFreddy
762
New contributor
Freddy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
Trying to learn coding in my 30s.
Could anybody review my code and give me some feedback if possible? It works, but I am sure there are better ways to solve this problem.
The problem:
A text is given. Write a program that modifies the casing of letters to uppercase at all places in the text surrounded by <upcase> and </upcase> tags. Tags cannot be nested.
Here is what I've come up with:
namespace Task6Casing
{
class Program
{
static void Main(string args)
{
Console.Write("Text: ");
string text = Console.ReadLine();
char textNew = new char[text.Length];
int i = 0, j = 0, k = 0;
while (i < text.Length)
{
if (text.IndexOf("<upcase>", k) < 0) // check if there is any <upcase> tag
{ // if no, copy everyting
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < text.IndexOf("<upcase>", k)) // if there is an <upcase> tag, copy letters until the tag
{
textNew[j++] = text[i++];
}
i += 8; // move index i to the position right next to the <upcase> tag
k = i;
}
if (text.IndexOf("</upcase>", k) < 0) // check if there is any </upcase> tag
{ // if no, copy everyting in CAPITAL letters
while (i < text.Length)
{
textNew[j++] = Char.ToUpper(text[i++]);
}
}
else
{
while (i < text.IndexOf("</upcase>", k)) // if there is an </upcase> tag, copy letters in CAP letters until the tag
{
textNew[j++] = Char.ToUpper(text[i++]);
}
i += 9; // move index i to the position right next to the </upcase> tag
}
}
foreach(char c in textNew)
{
Console.Write(c);
}
Console.WriteLine();
}
}
}
c# beginner strings console
c# beginner strings console
edited 2 days ago
Sᴀᴍ Onᴇᴌᴀ
9,95662166
asked 2 days ago
FreddyFreddy
762
New contributor
Freddy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 2 days ago
Sᴀᴍ Onᴇᴌᴀ
9,95662166
asked 2 days ago
FreddyFreddy
762
New contributor
Freddy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 2 days ago
Sᴀᴍ Onᴇᴌᴀ
9,95662166
edited 2 days ago
Sᴀᴍ Onᴇᴌᴀ
9,95662166
edited 2 days ago
Sᴀᴍ Onᴇᴌᴀ
9,95662166
9,95662166
asked 2 days ago
FreddyFreddy
762
New contributor
Freddy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 2 days ago
FreddyFreddy
762
asked 2 days ago
FreddyFreddy
762
762
New contributor
Freddy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Freddy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
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add a comment |
add a comment |
3 Answers
3
active
oldest
votes
7
$begingroup$
Your code is easy to understand and very performant.
Some improvements:
- String for start / end tag could be stored as constant. That has the advantage that it can be changed on one central location and the length of the string can be accessed like
i += START_TAG.Length
- When using a
StringBuilderinstead of of the char arraynewText, the running variable 'j' can be dropped. - The 2 code parts
if (text.IndexOf("<upcase>", k) < 0) // check if there is
any <upcase> tag
{ // if no, copy everyting
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < text.IndexOf("<upcase>", k)) // if there is an <upcase> tag, copy letters until the tag
{
textNew[j++] = text[i++];
}
i += 8; // move index i to the position right next to the <upcase> tag
k = i;
}
and
if (text.IndexOf("</upcase>", k) < 0) // check if there is any </upcase> tag
{ // if no, copy everyting in CAPITAL letters
while (i < text.Length)
{
textNew[j++] = Char.ToUpper(text[i++]);
}
}
else
{
while (i < text.IndexOf("</upcase>", k)) // if there is an </upcase> tag, copy letters in CAP letters until the tag
{
textNew[j++] = Char.ToUpper(text[i++]);
}
i += 9; // move index i to the position right next to the </upcase> tag
}
are very simlar. Probably it is possible to create one more generic code fragment that coveres both cases.
Since your solution is still understandable for such a simple use case, it will fast become unmaintainable if the use case becomes more complex. Therefore, it makes sense to think about a more abstract OOP concepts to model the solution.
One alternative impl. (that is probably over engineered for the given problem) gives an idea how a more object oriented design could look like:
public class Tag
{
private readonly Func<char, char> map;
public Tag(string start, string end, Func<char, char> map)
{
this.Start = start;
this.End = end;
this.map = map;
}
public string Start { get; }
public string End { get; }
public char Map(char input) => this.map(input);
}
public class TagProcessor
{
private readonly Tag tag;
private readonly StringBuilder output = new StringBuilder();
private string input;
private bool isTagOpen;
private int index;
public TagProcessor(Tag tag)
{
this.tag = tag;
}
public string Process(string input)
{
this.input = input;
this.index = 0;
this.isTagOpen = false;
this.output.Clear();
do
{
var tagProcessed = this.TryOpenTag() || this.TryCloseTag();
if (!tagProcessed)
{
this.ApplyCurrentChar();
}
}
while (this.MoveNext());
return output.ToString();
}
private bool IsEndTag() => input.IndexOf(tag.End, this.index) == this.index;
private bool IsStartTag() => input.IndexOf(tag.Start, this.index) == this.index;
private bool MoveNext()
{
index++;
return index < this.input.Length;
}
private void ApplyCurrentChar()
{
var inputChar = this.input[this.index];
var transfomed = this.isTagOpen ? tag.Map(inputChar) : inputChar;
this.output.Append(transfomed);
}
private bool TryOpenTag()
{
if (!isTagOpen && IsStartTag())
{
this.index += this.tag.Start.Length - 1;
this.isTagOpen = true;
return true;
}
return false;
}
private bool TryCloseTag()
{
if (isTagOpen && IsEndTag())
{
this.index += this.tag.End.Length - 1;
this.isTagOpen = false;
return true;
}
return false;
}
}
public static void Main(string args)
{
var processor = new TagProcessor(new Tag("<upcase>", "</upcase>", char.ToUpper));
var test = new
{
"abc<upcase>test</upcase>",
"abc<upcase>test",
"abc<upcase></upcase>test",
"abc<upcase>test</upcase>test",
"abc<upcase>te<upcase>st</upcase>test",
"a</upcase>bc<upcase>te<upcase>st</upcase>te</upcase>st",
};
foreach (var t in test)
Console.WriteLine(t + ": " + processor.Process(t));
Console.ReadLine();
}
The advantages are, that this solution remains readable if the complexity grows (e.g. more tags were added) and it allows to change / extend the logic without understanding the whole parsing logic. Further more, each method has a single pupose which increases comprehensibleness.
answered 2 days ago
JanDotNetJanDotNet
7,0131339
$endgroup$
add a comment |
4
$begingroup$
This loop
while (i < text.IndexOf("<upcase>", k))
{
....
}
invokes IndexOf multiple times for nothing. I'd call it just once and use the result:
const int upcasePos = text.IndexOf("<upcase>", k);
if (upcasePos < 0)
{
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < upcasePos)
{
textNew[j++] = text[i++];
}
....
}
Edit
You can also speed things up by getting rid of char-by-char iteration, and instead processing longer parts of the string at once with standard routines.
Here's an outline:
StringBuilder sb = new StringBuilder();
for (int k = 0; k < text.length; )
{
int tagOpen = text.IndexOf("<upcase>", k));
if (tagOpen < 0)
{
sb.Append(text.Substring(k)); // take the tail
break;
}
sb.Append(text.Substring(k, tagOpen - k));
k = tagOpen + 8; // skip the tag
int tagClose = text.IndexOf("</upcase>", k));
if (tagClose < 0)
{
sb.Append(text.Substring(k).toUpper()); // take the tail in upper case
break;
}
sb.Append(text.Substring(k, tagClose - k).toUpper());
k = tagClose + 9; // skip the tag
}
result = sb.ToString(); // return this
answered 2 days ago
CiaPanCiaPan
1,3621513
$endgroup$
add a comment |
3
$begingroup$
Below is a refactoring of your algorithm with some inline comments.
string Review(string text)
{
const string startTag = "<upcase>"; // Use declared string rather than string literals
const string endTag = "</upcase>";
// textNew is a somewhat "backward" name. result or newText would be better
char result = new char[text.Length];
// Instantiate each variable on a single line. It's easier to find and maintain
// Provide some meaningful names instead for i, j and k. (i, j and k may be alright in a lessser complex context, but here they easily lose their meaining through the loop)
int curIndex = 0;
int resultIndex = 0;
int searchIndex = 0;
while (curIndex < text.Length)
{
if (text.IndexOf(startTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = text[curIndex++];
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int startIndex = text.IndexOf(startTag, searchIndex);
while (curIndex < startIndex)
{
result[resultIndex++] = text[curIndex++];
}
curIndex += startTag.Length; // Use the length of the tag string instead of a magic number
searchIndex = curIndex;
}
if (text.IndexOf(endTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int endIndex = text.IndexOf(endTag, searchIndex);
while (curIndex < endIndex)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
curIndex += endTag.Length; // Use the length of the tag string instead of a magic number
}
}
// Return the result instead of write it to the console.
return new string(result.Take(resultIndex).ToArray()); // You have to truncate the char array in order to prevent a trailing new line
//OR: return new string(textNew).TrimEnd('');
}
Below is some other approaches that you may find useful for inspiration:
string ToUpperInTags(string text)
{
const string start = "<upcase>";
const string stop = "</upcase>";
List<string> fragments = new List<string>();
int curIndex = 0;
while (curIndex < text.Length)
{
int startIndex = text.IndexOf(start, curIndex);
if (startIndex >= 0)
{
fragments.Add(text.Substring(curIndex, startIndex - curIndex));
int stopIndex = text.IndexOf(stop, startIndex + start.Length);
if (stopIndex < 0) throw new InvalidOperationException($"Unpaired start at {startIndex}");
fragments.Add(text.Substring(startIndex + start.Length, stopIndex - (startIndex + start.Length)).ToUpper());
curIndex = stopIndex + stop.Length;
}
else
{
fragments.Add(text.Substring(curIndex));
break;
}
}
return string.Join("", fragments);
}
string ToUpperInTags2(string text)
{
string pattern = @"(?<start><upcase>)(?<content>[^<>]*)(?<stop></upcase>)?";
foreach (Match match in Regex.Matches(text, pattern))
{
text = Regex.Replace(text, $"{match.Groups["start"]}{match.Groups["content"]}{match.Groups["stop"]}", match.Groups["content"].Value.ToUpper());
}
return text;
}
string ToUpperInTags3(string text)
{
string pattern = @"<upcase>(?<content>[^<>]*)(</upcase>)?";
return Regex.Replace(text, pattern, m => m.Groups["content"].Value.ToUpper());
}
They don't all behave exactly as yours, and are just provided for inspiration for further study...
answered 2 days ago
Henrik HansenHenrik Hansen
8,11011231
$endgroup$
add a comment |
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3 Answers
3
active
oldest
votes
3 Answers
3
active
oldest
votes
active
oldest
votes
active
oldest
votes
7
$begingroup$
Your code is easy to understand and very performant.
Some improvements:
- String for start / end tag could be stored as constant. That has the advantage that it can be changed on one central location and the length of the string can be accessed like
i += START_TAG.Length
- When using a
StringBuilderinstead of of the char arraynewText, the running variable 'j' can be dropped. - The 2 code parts
if (text.IndexOf("<upcase>", k) < 0) // check if there is
any <upcase> tag
{ // if no, copy everyting
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < text.IndexOf("<upcase>", k)) // if there is an <upcase> tag, copy letters until the tag
{
textNew[j++] = text[i++];
}
i += 8; // move index i to the position right next to the <upcase> tag
k = i;
}
and
if (text.IndexOf("</upcase>", k) < 0) // check if there is any </upcase> tag
{ // if no, copy everyting in CAPITAL letters
while (i < text.Length)
{
textNew[j++] = Char.ToUpper(text[i++]);
}
}
else
{
while (i < text.IndexOf("</upcase>", k)) // if there is an </upcase> tag, copy letters in CAP letters until the tag
{
textNew[j++] = Char.ToUpper(text[i++]);
}
i += 9; // move index i to the position right next to the </upcase> tag
}
are very simlar. Probably it is possible to create one more generic code fragment that coveres both cases.
Since your solution is still understandable for such a simple use case, it will fast become unmaintainable if the use case becomes more complex. Therefore, it makes sense to think about a more abstract OOP concepts to model the solution.
One alternative impl. (that is probably over engineered for the given problem) gives an idea how a more object oriented design could look like:
public class Tag
{
private readonly Func<char, char> map;
public Tag(string start, string end, Func<char, char> map)
{
this.Start = start;
this.End = end;
this.map = map;
}
public string Start { get; }
public string End { get; }
public char Map(char input) => this.map(input);
}
public class TagProcessor
{
private readonly Tag tag;
private readonly StringBuilder output = new StringBuilder();
private string input;
private bool isTagOpen;
private int index;
public TagProcessor(Tag tag)
{
this.tag = tag;
}
public string Process(string input)
{
this.input = input;
this.index = 0;
this.isTagOpen = false;
this.output.Clear();
do
{
var tagProcessed = this.TryOpenTag() || this.TryCloseTag();
if (!tagProcessed)
{
this.ApplyCurrentChar();
}
}
while (this.MoveNext());
return output.ToString();
}
private bool IsEndTag() => input.IndexOf(tag.End, this.index) == this.index;
private bool IsStartTag() => input.IndexOf(tag.Start, this.index) == this.index;
private bool MoveNext()
{
index++;
return index < this.input.Length;
}
private void ApplyCurrentChar()
{
var inputChar = this.input[this.index];
var transfomed = this.isTagOpen ? tag.Map(inputChar) : inputChar;
this.output.Append(transfomed);
}
private bool TryOpenTag()
{
if (!isTagOpen && IsStartTag())
{
this.index += this.tag.Start.Length - 1;
this.isTagOpen = true;
return true;
}
return false;
}
private bool TryCloseTag()
{
if (isTagOpen && IsEndTag())
{
this.index += this.tag.End.Length - 1;
this.isTagOpen = false;
return true;
}
return false;
}
}
public static void Main(string args)
{
var processor = new TagProcessor(new Tag("<upcase>", "</upcase>", char.ToUpper));
var test = new
{
"abc<upcase>test</upcase>",
"abc<upcase>test",
"abc<upcase></upcase>test",
"abc<upcase>test</upcase>test",
"abc<upcase>te<upcase>st</upcase>test",
"a</upcase>bc<upcase>te<upcase>st</upcase>te</upcase>st",
};
foreach (var t in test)
Console.WriteLine(t + ": " + processor.Process(t));
Console.ReadLine();
}
The advantages are, that this solution remains readable if the complexity grows (e.g. more tags were added) and it allows to change / extend the logic without understanding the whole parsing logic. Further more, each method has a single pupose which increases comprehensibleness.
answered 2 days ago
JanDotNetJanDotNet
7,0131339
$endgroup$
add a comment |
7
$begingroup$
Your code is easy to understand and very performant.
Some improvements:
- String for start / end tag could be stored as constant. That has the advantage that it can be changed on one central location and the length of the string can be accessed like
i += START_TAG.Length
- When using a
StringBuilderinstead of of the char arraynewText, the running variable 'j' can be dropped. - The 2 code parts
if (text.IndexOf("<upcase>", k) < 0) // check if there is
any <upcase> tag
{ // if no, copy everyting
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < text.IndexOf("<upcase>", k)) // if there is an <upcase> tag, copy letters until the tag
{
textNew[j++] = text[i++];
}
i += 8; // move index i to the position right next to the <upcase> tag
k = i;
}
and
if (text.IndexOf("</upcase>", k) < 0) // check if there is any </upcase> tag
{ // if no, copy everyting in CAPITAL letters
while (i < text.Length)
{
textNew[j++] = Char.ToUpper(text[i++]);
}
}
else
{
while (i < text.IndexOf("</upcase>", k)) // if there is an </upcase> tag, copy letters in CAP letters until the tag
{
textNew[j++] = Char.ToUpper(text[i++]);
}
i += 9; // move index i to the position right next to the </upcase> tag
}
are very simlar. Probably it is possible to create one more generic code fragment that coveres both cases.
Since your solution is still understandable for such a simple use case, it will fast become unmaintainable if the use case becomes more complex. Therefore, it makes sense to think about a more abstract OOP concepts to model the solution.
One alternative impl. (that is probably over engineered for the given problem) gives an idea how a more object oriented design could look like:
public class Tag
{
private readonly Func<char, char> map;
public Tag(string start, string end, Func<char, char> map)
{
this.Start = start;
this.End = end;
this.map = map;
}
public string Start { get; }
public string End { get; }
public char Map(char input) => this.map(input);
}
public class TagProcessor
{
private readonly Tag tag;
private readonly StringBuilder output = new StringBuilder();
private string input;
private bool isTagOpen;
private int index;
public TagProcessor(Tag tag)
{
this.tag = tag;
}
public string Process(string input)
{
this.input = input;
this.index = 0;
this.isTagOpen = false;
this.output.Clear();
do
{
var tagProcessed = this.TryOpenTag() || this.TryCloseTag();
if (!tagProcessed)
{
this.ApplyCurrentChar();
}
}
while (this.MoveNext());
return output.ToString();
}
private bool IsEndTag() => input.IndexOf(tag.End, this.index) == this.index;
private bool IsStartTag() => input.IndexOf(tag.Start, this.index) == this.index;
private bool MoveNext()
{
index++;
return index < this.input.Length;
}
private void ApplyCurrentChar()
{
var inputChar = this.input[this.index];
var transfomed = this.isTagOpen ? tag.Map(inputChar) : inputChar;
this.output.Append(transfomed);
}
private bool TryOpenTag()
{
if (!isTagOpen && IsStartTag())
{
this.index += this.tag.Start.Length - 1;
this.isTagOpen = true;
return true;
}
return false;
}
private bool TryCloseTag()
{
if (isTagOpen && IsEndTag())
{
this.index += this.tag.End.Length - 1;
this.isTagOpen = false;
return true;
}
return false;
}
}
public static void Main(string args)
{
var processor = new TagProcessor(new Tag("<upcase>", "</upcase>", char.ToUpper));
var test = new
{
"abc<upcase>test</upcase>",
"abc<upcase>test",
"abc<upcase></upcase>test",
"abc<upcase>test</upcase>test",
"abc<upcase>te<upcase>st</upcase>test",
"a</upcase>bc<upcase>te<upcase>st</upcase>te</upcase>st",
};
foreach (var t in test)
Console.WriteLine(t + ": " + processor.Process(t));
Console.ReadLine();
}
The advantages are, that this solution remains readable if the complexity grows (e.g. more tags were added) and it allows to change / extend the logic without understanding the whole parsing logic. Further more, each method has a single pupose which increases comprehensibleness.
answered 2 days ago
JanDotNetJanDotNet
7,0131339
$endgroup$
add a comment |
7
7
7
$begingroup$
Your code is easy to understand and very performant.
Some improvements:
- String for start / end tag could be stored as constant. That has the advantage that it can be changed on one central location and the length of the string can be accessed like
i += START_TAG.Length
- When using a
StringBuilderinstead of of the char arraynewText, the running variable 'j' can be dropped. - The 2 code parts
if (text.IndexOf("<upcase>", k) < 0) // check if there is
any <upcase> tag
{ // if no, copy everyting
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < text.IndexOf("<upcase>", k)) // if there is an <upcase> tag, copy letters until the tag
{
textNew[j++] = text[i++];
}
i += 8; // move index i to the position right next to the <upcase> tag
k = i;
}
and
if (text.IndexOf("</upcase>", k) < 0) // check if there is any </upcase> tag
{ // if no, copy everyting in CAPITAL letters
while (i < text.Length)
{
textNew[j++] = Char.ToUpper(text[i++]);
}
}
else
{
while (i < text.IndexOf("</upcase>", k)) // if there is an </upcase> tag, copy letters in CAP letters until the tag
{
textNew[j++] = Char.ToUpper(text[i++]);
}
i += 9; // move index i to the position right next to the </upcase> tag
}
are very simlar. Probably it is possible to create one more generic code fragment that coveres both cases.
Since your solution is still understandable for such a simple use case, it will fast become unmaintainable if the use case becomes more complex. Therefore, it makes sense to think about a more abstract OOP concepts to model the solution.
One alternative impl. (that is probably over engineered for the given problem) gives an idea how a more object oriented design could look like:
public class Tag
{
private readonly Func<char, char> map;
public Tag(string start, string end, Func<char, char> map)
{
this.Start = start;
this.End = end;
this.map = map;
}
public string Start { get; }
public string End { get; }
public char Map(char input) => this.map(input);
}
public class TagProcessor
{
private readonly Tag tag;
private readonly StringBuilder output = new StringBuilder();
private string input;
private bool isTagOpen;
private int index;
public TagProcessor(Tag tag)
{
this.tag = tag;
}
public string Process(string input)
{
this.input = input;
this.index = 0;
this.isTagOpen = false;
this.output.Clear();
do
{
var tagProcessed = this.TryOpenTag() || this.TryCloseTag();
if (!tagProcessed)
{
this.ApplyCurrentChar();
}
}
while (this.MoveNext());
return output.ToString();
}
private bool IsEndTag() => input.IndexOf(tag.End, this.index) == this.index;
private bool IsStartTag() => input.IndexOf(tag.Start, this.index) == this.index;
private bool MoveNext()
{
index++;
return index < this.input.Length;
}
private void ApplyCurrentChar()
{
var inputChar = this.input[this.index];
var transfomed = this.isTagOpen ? tag.Map(inputChar) : inputChar;
this.output.Append(transfomed);
}
private bool TryOpenTag()
{
if (!isTagOpen && IsStartTag())
{
this.index += this.tag.Start.Length - 1;
this.isTagOpen = true;
return true;
}
return false;
}
private bool TryCloseTag()
{
if (isTagOpen && IsEndTag())
{
this.index += this.tag.End.Length - 1;
this.isTagOpen = false;
return true;
}
return false;
}
}
public static void Main(string args)
{
var processor = new TagProcessor(new Tag("<upcase>", "</upcase>", char.ToUpper));
var test = new
{
"abc<upcase>test</upcase>",
"abc<upcase>test",
"abc<upcase></upcase>test",
"abc<upcase>test</upcase>test",
"abc<upcase>te<upcase>st</upcase>test",
"a</upcase>bc<upcase>te<upcase>st</upcase>te</upcase>st",
};
foreach (var t in test)
Console.WriteLine(t + ": " + processor.Process(t));
Console.ReadLine();
}
The advantages are, that this solution remains readable if the complexity grows (e.g. more tags were added) and it allows to change / extend the logic without understanding the whole parsing logic. Further more, each method has a single pupose which increases comprehensibleness.
answered 2 days ago
JanDotNetJanDotNet
7,0131339
$endgroup$
Your code is easy to understand and very performant.
Some improvements:
- String for start / end tag could be stored as constant. That has the advantage that it can be changed on one central location and the length of the string can be accessed like
i += START_TAG.Length
- When using a
StringBuilderinstead of of the char arraynewText, the running variable 'j' can be dropped. - The 2 code parts
if (text.IndexOf("<upcase>", k) < 0) // check if there is
any <upcase> tag
{ // if no, copy everyting
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < text.IndexOf("<upcase>", k)) // if there is an <upcase> tag, copy letters until the tag
{
textNew[j++] = text[i++];
}
i += 8; // move index i to the position right next to the <upcase> tag
k = i;
}
and
if (text.IndexOf("</upcase>", k) < 0) // check if there is any </upcase> tag
{ // if no, copy everyting in CAPITAL letters
while (i < text.Length)
{
textNew[j++] = Char.ToUpper(text[i++]);
}
}
else
{
while (i < text.IndexOf("</upcase>", k)) // if there is an </upcase> tag, copy letters in CAP letters until the tag
{
textNew[j++] = Char.ToUpper(text[i++]);
}
i += 9; // move index i to the position right next to the </upcase> tag
}
are very simlar. Probably it is possible to create one more generic code fragment that coveres both cases.
Since your solution is still understandable for such a simple use case, it will fast become unmaintainable if the use case becomes more complex. Therefore, it makes sense to think about a more abstract OOP concepts to model the solution.
One alternative impl. (that is probably over engineered for the given problem) gives an idea how a more object oriented design could look like:
public class Tag
{
private readonly Func<char, char> map;
public Tag(string start, string end, Func<char, char> map)
{
this.Start = start;
this.End = end;
this.map = map;
}
public string Start { get; }
public string End { get; }
public char Map(char input) => this.map(input);
}
public class TagProcessor
{
private readonly Tag tag;
private readonly StringBuilder output = new StringBuilder();
private string input;
private bool isTagOpen;
private int index;
public TagProcessor(Tag tag)
{
this.tag = tag;
}
public string Process(string input)
{
this.input = input;
this.index = 0;
this.isTagOpen = false;
this.output.Clear();
do
{
var tagProcessed = this.TryOpenTag() || this.TryCloseTag();
if (!tagProcessed)
{
this.ApplyCurrentChar();
}
}
while (this.MoveNext());
return output.ToString();
}
private bool IsEndTag() => input.IndexOf(tag.End, this.index) == this.index;
private bool IsStartTag() => input.IndexOf(tag.Start, this.index) == this.index;
private bool MoveNext()
{
index++;
return index < this.input.Length;
}
private void ApplyCurrentChar()
{
var inputChar = this.input[this.index];
var transfomed = this.isTagOpen ? tag.Map(inputChar) : inputChar;
this.output.Append(transfomed);
}
private bool TryOpenTag()
{
if (!isTagOpen && IsStartTag())
{
this.index += this.tag.Start.Length - 1;
this.isTagOpen = true;
return true;
}
return false;
}
private bool TryCloseTag()
{
if (isTagOpen && IsEndTag())
{
this.index += this.tag.End.Length - 1;
this.isTagOpen = false;
return true;
}
return false;
}
}
public static void Main(string args)
{
var processor = new TagProcessor(new Tag("<upcase>", "</upcase>", char.ToUpper));
var test = new
{
"abc<upcase>test</upcase>",
"abc<upcase>test",
"abc<upcase></upcase>test",
"abc<upcase>test</upcase>test",
"abc<upcase>te<upcase>st</upcase>test",
"a</upcase>bc<upcase>te<upcase>st</upcase>te</upcase>st",
};
foreach (var t in test)
Console.WriteLine(t + ": " + processor.Process(t));
Console.ReadLine();
}
The advantages are, that this solution remains readable if the complexity grows (e.g. more tags were added) and it allows to change / extend the logic without understanding the whole parsing logic. Further more, each method has a single pupose which increases comprehensibleness.
answered 2 days ago
JanDotNetJanDotNet
7,0131339
edited 2 days ago
answered 2 days ago
JanDotNetJanDotNet
7,0131339
answered 2 days ago
JanDotNetJanDotNet
7,0131339
answered 2 days ago
JanDotNetJanDotNet
7,0131339
7,0131339
add a comment |
add a comment |
4
$begingroup$
This loop
while (i < text.IndexOf("<upcase>", k))
{
....
}
invokes IndexOf multiple times for nothing. I'd call it just once and use the result:
const int upcasePos = text.IndexOf("<upcase>", k);
if (upcasePos < 0)
{
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < upcasePos)
{
textNew[j++] = text[i++];
}
....
}
Edit
You can also speed things up by getting rid of char-by-char iteration, and instead processing longer parts of the string at once with standard routines.
Here's an outline:
StringBuilder sb = new StringBuilder();
for (int k = 0; k < text.length; )
{
int tagOpen = text.IndexOf("<upcase>", k));
if (tagOpen < 0)
{
sb.Append(text.Substring(k)); // take the tail
break;
}
sb.Append(text.Substring(k, tagOpen - k));
k = tagOpen + 8; // skip the tag
int tagClose = text.IndexOf("</upcase>", k));
if (tagClose < 0)
{
sb.Append(text.Substring(k).toUpper()); // take the tail in upper case
break;
}
sb.Append(text.Substring(k, tagClose - k).toUpper());
k = tagClose + 9; // skip the tag
}
result = sb.ToString(); // return this
answered 2 days ago
CiaPanCiaPan
1,3621513
$endgroup$
add a comment |
4
$begingroup$
This loop
while (i < text.IndexOf("<upcase>", k))
{
....
}
invokes IndexOf multiple times for nothing. I'd call it just once and use the result:
const int upcasePos = text.IndexOf("<upcase>", k);
if (upcasePos < 0)
{
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < upcasePos)
{
textNew[j++] = text[i++];
}
....
}
Edit
You can also speed things up by getting rid of char-by-char iteration, and instead processing longer parts of the string at once with standard routines.
Here's an outline:
StringBuilder sb = new StringBuilder();
for (int k = 0; k < text.length; )
{
int tagOpen = text.IndexOf("<upcase>", k));
if (tagOpen < 0)
{
sb.Append(text.Substring(k)); // take the tail
break;
}
sb.Append(text.Substring(k, tagOpen - k));
k = tagOpen + 8; // skip the tag
int tagClose = text.IndexOf("</upcase>", k));
if (tagClose < 0)
{
sb.Append(text.Substring(k).toUpper()); // take the tail in upper case
break;
}
sb.Append(text.Substring(k, tagClose - k).toUpper());
k = tagClose + 9; // skip the tag
}
result = sb.ToString(); // return this
answered 2 days ago
CiaPanCiaPan
1,3621513
$endgroup$
add a comment |
4
4
4
$begingroup$
This loop
while (i < text.IndexOf("<upcase>", k))
{
....
}
invokes IndexOf multiple times for nothing. I'd call it just once and use the result:
const int upcasePos = text.IndexOf("<upcase>", k);
if (upcasePos < 0)
{
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < upcasePos)
{
textNew[j++] = text[i++];
}
....
}
Edit
You can also speed things up by getting rid of char-by-char iteration, and instead processing longer parts of the string at once with standard routines.
Here's an outline:
StringBuilder sb = new StringBuilder();
for (int k = 0; k < text.length; )
{
int tagOpen = text.IndexOf("<upcase>", k));
if (tagOpen < 0)
{
sb.Append(text.Substring(k)); // take the tail
break;
}
sb.Append(text.Substring(k, tagOpen - k));
k = tagOpen + 8; // skip the tag
int tagClose = text.IndexOf("</upcase>", k));
if (tagClose < 0)
{
sb.Append(text.Substring(k).toUpper()); // take the tail in upper case
break;
}
sb.Append(text.Substring(k, tagClose - k).toUpper());
k = tagClose + 9; // skip the tag
}
result = sb.ToString(); // return this
answered 2 days ago
CiaPanCiaPan
1,3621513
$endgroup$
This loop
while (i < text.IndexOf("<upcase>", k))
{
....
}
invokes IndexOf multiple times for nothing. I'd call it just once and use the result:
const int upcasePos = text.IndexOf("<upcase>", k);
if (upcasePos < 0)
{
while (i < text.Length)
{
textNew[j++] = text[i++];
}
}
else
{
while (i < upcasePos)
{
textNew[j++] = text[i++];
}
....
}
Edit
You can also speed things up by getting rid of char-by-char iteration, and instead processing longer parts of the string at once with standard routines.
Here's an outline:
StringBuilder sb = new StringBuilder();
for (int k = 0; k < text.length; )
{
int tagOpen = text.IndexOf("<upcase>", k));
if (tagOpen < 0)
{
sb.Append(text.Substring(k)); // take the tail
break;
}
sb.Append(text.Substring(k, tagOpen - k));
k = tagOpen + 8; // skip the tag
int tagClose = text.IndexOf("</upcase>", k));
if (tagClose < 0)
{
sb.Append(text.Substring(k).toUpper()); // take the tail in upper case
break;
}
sb.Append(text.Substring(k, tagClose - k).toUpper());
k = tagClose + 9; // skip the tag
}
result = sb.ToString(); // return this
answered 2 days ago
CiaPanCiaPan
1,3621513
edited 2 days ago
answered 2 days ago
CiaPanCiaPan
1,3621513
answered 2 days ago
CiaPanCiaPan
1,3621513
answered 2 days ago
CiaPanCiaPan
1,3621513
1,3621513
add a comment |
add a comment |
3
$begingroup$
Below is a refactoring of your algorithm with some inline comments.
string Review(string text)
{
const string startTag = "<upcase>"; // Use declared string rather than string literals
const string endTag = "</upcase>";
// textNew is a somewhat "backward" name. result or newText would be better
char result = new char[text.Length];
// Instantiate each variable on a single line. It's easier to find and maintain
// Provide some meaningful names instead for i, j and k. (i, j and k may be alright in a lessser complex context, but here they easily lose their meaining through the loop)
int curIndex = 0;
int resultIndex = 0;
int searchIndex = 0;
while (curIndex < text.Length)
{
if (text.IndexOf(startTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = text[curIndex++];
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int startIndex = text.IndexOf(startTag, searchIndex);
while (curIndex < startIndex)
{
result[resultIndex++] = text[curIndex++];
}
curIndex += startTag.Length; // Use the length of the tag string instead of a magic number
searchIndex = curIndex;
}
if (text.IndexOf(endTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int endIndex = text.IndexOf(endTag, searchIndex);
while (curIndex < endIndex)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
curIndex += endTag.Length; // Use the length of the tag string instead of a magic number
}
}
// Return the result instead of write it to the console.
return new string(result.Take(resultIndex).ToArray()); // You have to truncate the char array in order to prevent a trailing new line
//OR: return new string(textNew).TrimEnd('');
}
Below is some other approaches that you may find useful for inspiration:
string ToUpperInTags(string text)
{
const string start = "<upcase>";
const string stop = "</upcase>";
List<string> fragments = new List<string>();
int curIndex = 0;
while (curIndex < text.Length)
{
int startIndex = text.IndexOf(start, curIndex);
if (startIndex >= 0)
{
fragments.Add(text.Substring(curIndex, startIndex - curIndex));
int stopIndex = text.IndexOf(stop, startIndex + start.Length);
if (stopIndex < 0) throw new InvalidOperationException($"Unpaired start at {startIndex}");
fragments.Add(text.Substring(startIndex + start.Length, stopIndex - (startIndex + start.Length)).ToUpper());
curIndex = stopIndex + stop.Length;
}
else
{
fragments.Add(text.Substring(curIndex));
break;
}
}
return string.Join("", fragments);
}
string ToUpperInTags2(string text)
{
string pattern = @"(?<start><upcase>)(?<content>[^<>]*)(?<stop></upcase>)?";
foreach (Match match in Regex.Matches(text, pattern))
{
text = Regex.Replace(text, $"{match.Groups["start"]}{match.Groups["content"]}{match.Groups["stop"]}", match.Groups["content"].Value.ToUpper());
}
return text;
}
string ToUpperInTags3(string text)
{
string pattern = @"<upcase>(?<content>[^<>]*)(</upcase>)?";
return Regex.Replace(text, pattern, m => m.Groups["content"].Value.ToUpper());
}
They don't all behave exactly as yours, and are just provided for inspiration for further study...
answered 2 days ago
Henrik HansenHenrik Hansen
8,11011231
$endgroup$
add a comment |
3
$begingroup$
Below is a refactoring of your algorithm with some inline comments.
string Review(string text)
{
const string startTag = "<upcase>"; // Use declared string rather than string literals
const string endTag = "</upcase>";
// textNew is a somewhat "backward" name. result or newText would be better
char result = new char[text.Length];
// Instantiate each variable on a single line. It's easier to find and maintain
// Provide some meaningful names instead for i, j and k. (i, j and k may be alright in a lessser complex context, but here they easily lose their meaining through the loop)
int curIndex = 0;
int resultIndex = 0;
int searchIndex = 0;
while (curIndex < text.Length)
{
if (text.IndexOf(startTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = text[curIndex++];
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int startIndex = text.IndexOf(startTag, searchIndex);
while (curIndex < startIndex)
{
result[resultIndex++] = text[curIndex++];
}
curIndex += startTag.Length; // Use the length of the tag string instead of a magic number
searchIndex = curIndex;
}
if (text.IndexOf(endTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int endIndex = text.IndexOf(endTag, searchIndex);
while (curIndex < endIndex)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
curIndex += endTag.Length; // Use the length of the tag string instead of a magic number
}
}
// Return the result instead of write it to the console.
return new string(result.Take(resultIndex).ToArray()); // You have to truncate the char array in order to prevent a trailing new line
//OR: return new string(textNew).TrimEnd('');
}
Below is some other approaches that you may find useful for inspiration:
string ToUpperInTags(string text)
{
const string start = "<upcase>";
const string stop = "</upcase>";
List<string> fragments = new List<string>();
int curIndex = 0;
while (curIndex < text.Length)
{
int startIndex = text.IndexOf(start, curIndex);
if (startIndex >= 0)
{
fragments.Add(text.Substring(curIndex, startIndex - curIndex));
int stopIndex = text.IndexOf(stop, startIndex + start.Length);
if (stopIndex < 0) throw new InvalidOperationException($"Unpaired start at {startIndex}");
fragments.Add(text.Substring(startIndex + start.Length, stopIndex - (startIndex + start.Length)).ToUpper());
curIndex = stopIndex + stop.Length;
}
else
{
fragments.Add(text.Substring(curIndex));
break;
}
}
return string.Join("", fragments);
}
string ToUpperInTags2(string text)
{
string pattern = @"(?<start><upcase>)(?<content>[^<>]*)(?<stop></upcase>)?";
foreach (Match match in Regex.Matches(text, pattern))
{
text = Regex.Replace(text, $"{match.Groups["start"]}{match.Groups["content"]}{match.Groups["stop"]}", match.Groups["content"].Value.ToUpper());
}
return text;
}
string ToUpperInTags3(string text)
{
string pattern = @"<upcase>(?<content>[^<>]*)(</upcase>)?";
return Regex.Replace(text, pattern, m => m.Groups["content"].Value.ToUpper());
}
They don't all behave exactly as yours, and are just provided for inspiration for further study...
answered 2 days ago
Henrik HansenHenrik Hansen
8,11011231
$endgroup$
add a comment |
3
3
3
$begingroup$
Below is a refactoring of your algorithm with some inline comments.
string Review(string text)
{
const string startTag = "<upcase>"; // Use declared string rather than string literals
const string endTag = "</upcase>";
// textNew is a somewhat "backward" name. result or newText would be better
char result = new char[text.Length];
// Instantiate each variable on a single line. It's easier to find and maintain
// Provide some meaningful names instead for i, j and k. (i, j and k may be alright in a lessser complex context, but here they easily lose their meaining through the loop)
int curIndex = 0;
int resultIndex = 0;
int searchIndex = 0;
while (curIndex < text.Length)
{
if (text.IndexOf(startTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = text[curIndex++];
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int startIndex = text.IndexOf(startTag, searchIndex);
while (curIndex < startIndex)
{
result[resultIndex++] = text[curIndex++];
}
curIndex += startTag.Length; // Use the length of the tag string instead of a magic number
searchIndex = curIndex;
}
if (text.IndexOf(endTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int endIndex = text.IndexOf(endTag, searchIndex);
while (curIndex < endIndex)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
curIndex += endTag.Length; // Use the length of the tag string instead of a magic number
}
}
// Return the result instead of write it to the console.
return new string(result.Take(resultIndex).ToArray()); // You have to truncate the char array in order to prevent a trailing new line
//OR: return new string(textNew).TrimEnd('');
}
Below is some other approaches that you may find useful for inspiration:
string ToUpperInTags(string text)
{
const string start = "<upcase>";
const string stop = "</upcase>";
List<string> fragments = new List<string>();
int curIndex = 0;
while (curIndex < text.Length)
{
int startIndex = text.IndexOf(start, curIndex);
if (startIndex >= 0)
{
fragments.Add(text.Substring(curIndex, startIndex - curIndex));
int stopIndex = text.IndexOf(stop, startIndex + start.Length);
if (stopIndex < 0) throw new InvalidOperationException($"Unpaired start at {startIndex}");
fragments.Add(text.Substring(startIndex + start.Length, stopIndex - (startIndex + start.Length)).ToUpper());
curIndex = stopIndex + stop.Length;
}
else
{
fragments.Add(text.Substring(curIndex));
break;
}
}
return string.Join("", fragments);
}
string ToUpperInTags2(string text)
{
string pattern = @"(?<start><upcase>)(?<content>[^<>]*)(?<stop></upcase>)?";
foreach (Match match in Regex.Matches(text, pattern))
{
text = Regex.Replace(text, $"{match.Groups["start"]}{match.Groups["content"]}{match.Groups["stop"]}", match.Groups["content"].Value.ToUpper());
}
return text;
}
string ToUpperInTags3(string text)
{
string pattern = @"<upcase>(?<content>[^<>]*)(</upcase>)?";
return Regex.Replace(text, pattern, m => m.Groups["content"].Value.ToUpper());
}
They don't all behave exactly as yours, and are just provided for inspiration for further study...
answered 2 days ago
Henrik HansenHenrik Hansen
8,11011231
$endgroup$
Below is a refactoring of your algorithm with some inline comments.
string Review(string text)
{
const string startTag = "<upcase>"; // Use declared string rather than string literals
const string endTag = "</upcase>";
// textNew is a somewhat "backward" name. result or newText would be better
char result = new char[text.Length];
// Instantiate each variable on a single line. It's easier to find and maintain
// Provide some meaningful names instead for i, j and k. (i, j and k may be alright in a lessser complex context, but here they easily lose their meaining through the loop)
int curIndex = 0;
int resultIndex = 0;
int searchIndex = 0;
while (curIndex < text.Length)
{
if (text.IndexOf(startTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = text[curIndex++];
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int startIndex = text.IndexOf(startTag, searchIndex);
while (curIndex < startIndex)
{
result[resultIndex++] = text[curIndex++];
}
curIndex += startTag.Length; // Use the length of the tag string instead of a magic number
searchIndex = curIndex;
}
if (text.IndexOf(endTag, searchIndex) < 0)
{
while (curIndex < text.Length)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
}
else
{
// Repeatedly calling the same function with the same values is inefficient
int endIndex = text.IndexOf(endTag, searchIndex);
while (curIndex < endIndex)
{
result[resultIndex++] = Char.ToUpper(text[curIndex++]);
}
curIndex += endTag.Length; // Use the length of the tag string instead of a magic number
}
}
// Return the result instead of write it to the console.
return new string(result.Take(resultIndex).ToArray()); // You have to truncate the char array in order to prevent a trailing new line
//OR: return new string(textNew).TrimEnd('');
}
Below is some other approaches that you may find useful for inspiration:
string ToUpperInTags(string text)
{
const string start = "<upcase>";
const string stop = "</upcase>";
List<string> fragments = new List<string>();
int curIndex = 0;
while (curIndex < text.Length)
{
int startIndex = text.IndexOf(start, curIndex);
if (startIndex >= 0)
{
fragments.Add(text.Substring(curIndex, startIndex - curIndex));
int stopIndex = text.IndexOf(stop, startIndex + start.Length);
if (stopIndex < 0) throw new InvalidOperationException($"Unpaired start at {startIndex}");
fragments.Add(text.Substring(startIndex + start.Length, stopIndex - (startIndex + start.Length)).ToUpper());
curIndex = stopIndex + stop.Length;
}
else
{
fragments.Add(text.Substring(curIndex));
break;
}
}
return string.Join("", fragments);
}
string ToUpperInTags2(string text)
{
string pattern = @"(?<start><upcase>)(?<content>[^<>]*)(?<stop></upcase>)?";
foreach (Match match in Regex.Matches(text, pattern))
{
text = Regex.Replace(text, $"{match.Groups["start"]}{match.Groups["content"]}{match.Groups["stop"]}", match.Groups["content"].Value.ToUpper());
}
return text;
}
string ToUpperInTags3(string text)
{
string pattern = @"<upcase>(?<content>[^<>]*)(</upcase>)?";
return Regex.Replace(text, pattern, m => m.Groups["content"].Value.ToUpper());
}
They don't all behave exactly as yours, and are just provided for inspiration for further study...
answered 2 days ago
Henrik HansenHenrik Hansen
8,11011231
edited 2 days ago
answered 2 days ago
Henrik HansenHenrik Hansen
8,11011231
answered 2 days ago
Henrik HansenHenrik Hansen
8,11011231
answered 2 days ago
Henrik HansenHenrik Hansen
8,11011231
8,11011231
add a comment |
add a comment |
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Freddy is a new contributor. Be nice, and check out our Code of Conduct.
Freddy is a new contributor. Be nice, and check out our Code of Conduct.
Freddy is a new contributor. Be nice, and check out our Code of Conduct.
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