[c#] How do I extract text that lies between parentheses (round brackets)?

I have a string User name (sales) and I want to extract the text between the brackets, how would I do this?

I suspect sub-string but I can't work out how to read until the closing bracket, the length of text will vary.

I came across this while I was looking for a solution to a very similar implementation.

Here is a snippet from my actual code. Starts substring from the first char (index 0).

 string separator = "\n";     //line terminator

 string output;
 string input= "HowAreYou?\nLets go there!";

 output = input.Substring(0, input.IndexOf(separator)); 

Much similar to @Gustavo Baiocchi Costa but offset is being calculated with another intermediate Substring.

int innerTextStart = input.IndexOf("(") + 1;
int innerTextLength = input.Substring(start).IndexOf(")");
string output = input.Substring(innerTextStart, innerTextLength);

input.Remove(input.IndexOf(')')).Substring(input.IndexOf('(') + 1);

Here is a general purpose readable function that avoids using regex:

// Returns the text between 'start' and 'end'.
string ExtractBetween(string text, string start, string end)
{
  int iStart = text.IndexOf(start);
  iStart = (iStart == -1) ? 0 : iStart + start.Length;
  int iEnd = text.LastIndexOf(end);
  if(iEnd == -1)
  {
    iEnd = text.Length;
  }
  int len = iEnd - iStart;

  return text.Substring(iStart, len);
}

To call it in your particular example you can do:

string result = ExtractBetween("User name (sales)", "(", ")");

input.Remove(input.IndexOf(')')).Substring(input.IndexOf('(') + 1);

The regex method is superior I think, but if you wanted to use the humble substring

string input= "my name is (Jayne C)";
int start = input.IndexOf("(");
int stop = input.IndexOf(")");
string output = input.Substring(start+1, stop - start - 1);

or

string input = "my name is (Jayne C)";
string output  = input.Substring(input.IndexOf("(") +1, input.IndexOf(")")- input.IndexOf("(")- 1);

input.Remove(input.IndexOf(')')).Substring(input.IndexOf('(') + 1);

string input = "User name (sales)";

string output = input.Substring(input.IndexOf('(') + 1, input.IndexOf(')') - input.IndexOf('(') - 1);

A regex maybe? I think this would work...

\(([a-z]+?)\)

If you wish to stay away from regular expressions, the simplest way I can think of is:

string input = "User name (sales)";
string output = input.Split('(', ')')[1];

Assuming that you only have one pair of parenthesis.

string s = "User name (sales)";
int start = s.IndexOf("(") + 1;
int end = s.IndexOf(")", start);
string result = s.Substring(start, end - start);

Use a Regular Expression:

string test = "(test)"; 
string word = Regex.Match(test, @"\((\w+)\)").Groups[1].Value;
Console.WriteLine(word);

Use this function:

public string GetSubstringByString(string a, string b, string c)
    {
        return c.Substring((c.IndexOf(a) + a.Length), (c.IndexOf(b) - c.IndexOf(a) - a.Length));
    }

and here is the usage:

GetSubstringByString("(", ")", "User name (sales)")

and the output would be:

sales

Assuming that you only have one pair of parenthesis.

string s = "User name (sales)";
int start = s.IndexOf("(") + 1;
int end = s.IndexOf(")", start);
string result = s.Substring(start, end - start);

Regular expressions might be the best tool here. If you are not famililar with them, I recommend you install Expresso - a great little regex tool.

Something like:

Regex regex = new Regex("\\((?<TextInsideBrackets>\\w+)\\)");
string incomingValue = "Username (sales)";
string insideBrackets = null;
Match match = regex.Match(incomingValue);
if(match.Success)
{
    insideBrackets = match.Groups["TextInsideBrackets"].Value;
}

The regex method is superior I think, but if you wanted to use the humble substring

string input= "my name is (Jayne C)";
int start = input.IndexOf("(");
int stop = input.IndexOf(")");
string output = input.Substring(start+1, stop - start - 1);

or

string input = "my name is (Jayne C)";
string output  = input.Substring(input.IndexOf("(") +1, input.IndexOf(")")- input.IndexOf("(")- 1);

using System;
using System.Text.RegularExpressions;

private IEnumerable<string> GetSubStrings(string input, string start, string end)
{
    Regex r = new Regex(Regex.Escape(start) +`"(.*?)"`  + Regex.Escape(end));
    MatchCollection matches = r.Matches(input);
    foreach (Match match in matches)
    yield return match.Groups[1].Value;
}

This code is faster than most solutions here (if not all), packed as String extension method, it does not support recursive nesting:

public static string GetNestedString(this string str, char start, char end)
{
    int s = -1;
    int i = -1;
    while (++i < str.Length)
        if (str[i] == start)
        {
            s = i;
            break;
        }
    int e = -1;
    while(++i < str.Length)
        if (str[i] == end)
        {
            e = i;
            break;
        }
    if (e > s)
        return str.Substring(s + 1, e - s - 1);
    return null;
}

This one is little longer and slower, but it handles recursive nesting more nicely:

public static string GetNestedString(this string str, char start, char end)
{
    int s = -1;
    int i = -1;
    while (++i < str.Length)
        if (str[i] == start)
        {
            s = i;
            break;
        }
    int e = -1;
    int depth = 0;
    while (++i < str.Length)
        if (str[i] == end)
        {
            e = i;
            if (depth == 0)
                break;
            else
                --depth;
        }
        else if (str[i] == start)
            ++depth;
    if (e > s)
        return str.Substring(s + 1, e - s - 1);
    return null;
}

Use a Regular Expression:

string test = "(test)"; 
string word = Regex.Match(test, @"\((\w+)\)").Groups[1].Value;
Console.WriteLine(word);

I'm finding that regular expressions are extremely useful but very difficult to write. So, I did some research and found this tool that makes writing them so easy.

Don't shy away from them because the syntax is difficult to figure out. They can be so powerful.

string input = "User name (sales)";

string output = input.Substring(input.IndexOf('(') + 1, input.IndexOf(')') - input.IndexOf('(') - 1);

int start = input.IndexOf("(") + 1;
int length = input.IndexOf(")") - start;
output = input.Substring(start, length);

Assuming that you only have one pair of parenthesis.

string s = "User name (sales)";
int start = s.IndexOf("(") + 1;
int end = s.IndexOf(")", start);
string result = s.Substring(start, end - start);

Use this function:

public string GetSubstringByString(string a, string b, string c)
    {
        return c.Substring((c.IndexOf(a) + a.Length), (c.IndexOf(b) - c.IndexOf(a) - a.Length));
    }

and here is the usage:

GetSubstringByString("(", ")", "User name (sales)")

and the output would be:

sales

Regular expressions might be the best tool here. If you are not famililar with them, I recommend you install Expresso - a great little regex tool.

Something like:

Regex regex = new Regex("\\((?<TextInsideBrackets>\\w+)\\)");
string incomingValue = "Username (sales)";
string insideBrackets = null;
Match match = regex.Match(incomingValue);
if(match.Success)
{
    insideBrackets = match.Groups["TextInsideBrackets"].Value;
}

int start = input.IndexOf("(") + 1;
int length = input.IndexOf(")") - start;
output = input.Substring(start, length);

I came across this while I was looking for a solution to a very similar implementation.

Here is a snippet from my actual code. Starts substring from the first char (index 0).

 string separator = "\n";     //line terminator

 string output;
 string input= "HowAreYou?\nLets go there!";

 output = input.Substring(0, input.IndexOf(separator)); 

Assuming that you only have one pair of parenthesis.

string s = "User name (sales)";
int start = s.IndexOf("(") + 1;
int end = s.IndexOf(")", start);
string result = s.Substring(start, end - start);

If you wish to stay away from regular expressions, the simplest way I can think of is:

string input = "User name (sales)";
string output = input.Split('(', ')')[1];

Regular expressions might be the best tool here. If you are not famililar with them, I recommend you install Expresso - a great little regex tool.

Something like:

Regex regex = new Regex("\\((?<TextInsideBrackets>\\w+)\\)");
string incomingValue = "Username (sales)";
string insideBrackets = null;
Match match = regex.Match(incomingValue);
if(match.Success)
{
    insideBrackets = match.Groups["TextInsideBrackets"].Value;
}

string input = "User name (sales)";

string output = input.Substring(input.IndexOf('(') + 1, input.IndexOf(')') - input.IndexOf('(') - 1);

I'm finding that regular expressions are extremely useful but very difficult to write. So, I did some research and found this tool that makes writing them so easy.

Don't shy away from them because the syntax is difficult to figure out. They can be so powerful.

using System;
using System.Text.RegularExpressions;

private IEnumerable<string> GetSubStrings(string input, string start, string end)
{
    Regex r = new Regex(Regex.Escape(start) +`"(.*?)"`  + Regex.Escape(end));
    MatchCollection matches = r.Matches(input);
    foreach (Match match in matches)
    yield return match.Groups[1].Value;
}

string input = "User name (sales)";

string output = input.Substring(input.IndexOf('(') + 1, input.IndexOf(')') - input.IndexOf('(') - 1);

Use a Regular Expression:

string test = "(test)"; 
string word = Regex.Match(test, @"\((\w+)\)").Groups[1].Value;
Console.WriteLine(word);

A very simple way to do it is by using regular expressions:

Regex.Match("User name (sales)", @"\(([^)]*)\)").Groups[1].Value

As a response to the (very funny) comment, here's the same Regex with some explanation:

\(             # Escaped parenthesis, means "starts with a '(' character"
    (          # Parentheses in a regex mean "put (capture) the stuff 
               #     in between into the Groups array" 
       [^)]    # Any character that is not a ')' character
       *       # Zero or more occurrences of the aforementioned "non ')' char"
    )          # Close the capturing group
\)             # "Ends with a ')' character"

The regex method is superior I think, but if you wanted to use the humble substring

string input= "my name is (Jayne C)";
int start = input.IndexOf("(");
int stop = input.IndexOf(")");
string output = input.Substring(start+1, stop - start - 1);

or

string input = "my name is (Jayne C)";
string output  = input.Substring(input.IndexOf("(") +1, input.IndexOf(")")- input.IndexOf("(")- 1);

Here is a general purpose readable function that avoids using regex:

// Returns the text between 'start' and 'end'.
string ExtractBetween(string text, string start, string end)
{
  int iStart = text.IndexOf(start);
  iStart = (iStart == -1) ? 0 : iStart + start.Length;
  int iEnd = text.LastIndexOf(end);
  if(iEnd == -1)
  {
    iEnd = text.Length;
  }
  int len = iEnd - iStart;

  return text.Substring(iStart, len);
}

To call it in your particular example you can do:

string result = ExtractBetween("User name (sales)", "(", ")");

Much similar to @Gustavo Baiocchi Costa but offset is being calculated with another intermediate Substring.

int innerTextStart = input.IndexOf("(") + 1;
int innerTextLength = input.Substring(start).IndexOf(")");
string output = input.Substring(innerTextStart, innerTextLength);

Use a Regular Expression:

string test = "(test)"; 
string word = Regex.Match(test, @"\((\w+)\)").Groups[1].Value;
Console.WriteLine(word);

A regex maybe? I think this would work...

\(([a-z]+?)\)

This code is faster than most solutions here (if not all), packed as String extension method, it does not support recursive nesting:

public static string GetNestedString(this string str, char start, char end)
{
    int s = -1;
    int i = -1;
    while (++i < str.Length)
        if (str[i] == start)
        {
            s = i;
            break;
        }
    int e = -1;
    while(++i < str.Length)
        if (str[i] == end)
        {
            e = i;
            break;
        }
    if (e > s)
        return str.Substring(s + 1, e - s - 1);
    return null;
}

This one is little longer and slower, but it handles recursive nesting more nicely:

public static string GetNestedString(this string str, char start, char end)
{
    int s = -1;
    int i = -1;
    while (++i < str.Length)
        if (str[i] == start)
        {
            s = i;
            break;
        }
    int e = -1;
    int depth = 0;
    while (++i < str.Length)
        if (str[i] == end)
        {
            e = i;
            if (depth == 0)
                break;
            else
                --depth;
        }
        else if (str[i] == start)
            ++depth;
    if (e > s)
        return str.Substring(s + 1, e - s - 1);
    return null;
}

A regex maybe? I think this would work...

\(([a-z]+?)\)

input.Remove(input.IndexOf(')')).Substring(input.IndexOf('(') + 1);

A very simple way to do it is by using regular expressions:

Regex.Match("User name (sales)", @"\(([^)]*)\)").Groups[1].Value

As a response to the (very funny) comment, here's the same Regex with some explanation:

\(             # Escaped parenthesis, means "starts with a '(' character"
    (          # Parentheses in a regex mean "put (capture) the stuff 
               #     in between into the Groups array" 
       [^)]    # Any character that is not a ')' character
       *       # Zero or more occurrences of the aforementioned "non ')' char"
    )          # Close the capturing group
\)             # "Ends with a ')' character"

Regular expressions might be the best tool here. If you are not famililar with them, I recommend you install Expresso - a great little regex tool.

Something like:

Regex regex = new Regex("\\((?<TextInsideBrackets>\\w+)\\)");
string incomingValue = "Username (sales)";
string insideBrackets = null;
Match match = regex.Match(incomingValue);
if(match.Success)
{
    insideBrackets = match.Groups["TextInsideBrackets"].Value;
}

A very simple way to do it is by using regular expressions:

Regex.Match("User name (sales)", @"\(([^)]*)\)").Groups[1].Value

As a response to the (very funny) comment, here's the same Regex with some explanation:

\(             # Escaped parenthesis, means "starts with a '(' character"
    (          # Parentheses in a regex mean "put (capture) the stuff 
               #     in between into the Groups array" 
       [^)]    # Any character that is not a ')' character
       *       # Zero or more occurrences of the aforementioned "non ')' char"
    )          # Close the capturing group
\)             # "Ends with a ')' character"

The regex method is superior I think, but if you wanted to use the humble substring

string input= "my name is (Jayne C)";
int start = input.IndexOf("(");
int stop = input.IndexOf(")");
string output = input.Substring(start+1, stop - start - 1);

or

string input = "my name is (Jayne C)";
string output  = input.Substring(input.IndexOf("(") +1, input.IndexOf(")")- input.IndexOf("(")- 1);