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Remove delimiter using C#

I Have a string as开发者_开发百科 follows:

{a{b,c}d}

if i give 1, the string must be displayed as:

{a d} 

the content within inner braces should be removed along with the braces.

Can anyone help me with it?


To extract the inner grouping of {} use the following regular expression:

string extract = Regex.Replace(source, "\{\w(\{\w,\w\})\w\}", "$1");

Actually, if you want to remove the comma....

string extract = Regex.Replace(source, "\{\w\{(\w),(\w)\}\w\}", "{$1 $2}");

To extract the outer without the inner grouping:

string extract = Regex.Replace(source, "(\{\w)\{\w,\w\}(\w\})", "$1 $2");

if in your example a, b, c, d are not literally single characters, that is groups of letters or even spaces, etc replace \w with \w+ or even .*

based on your comment on nesting....

string extract = Regex.Replace(source, "(\{\w)\{.*\}(\w\})\w*", "$1 $2");


go the regex-way above... it's really more beautiful!


you could do it by hand... i've written something for paranthesis in an example a few years ago... have to look for it a sec...:

     string def = "1+2*(3/(4+5))*2";
     int pcnt = 0, start = -1, end = -1;
     bool subEx = false;
     if(def.Contains("(") || def.Contains(")"))
        for(int i = 0; i < def.Length; i++) {
           if(def[i] == '(') {
              pcnt++;
              if(!subEx)
                 start = i;
           } else if(def[i] == ')')
              pcnt--;
           if(pcnt < 0)
              throw new Exception("negative paranthesis count...");
           if(pcnt != 0)
              subEx = true;
           if(subEx && pcnt == 0 && end == -1)
              end = i;
        }
     if(pcnt != 0) {
        throw new Exception("paranthesis doesn't match...");
     }
     if(subEx) {
        string firstPart = def.Substring(0, start);
        string innerPart = def.Substring(start + 1, end - (start + 1));
        string secondPart = def.Substring(end + 1);
        Console.WriteLine(firstPart);
        Console.WriteLine(innerPart);
        Console.WriteLine(secondPart);
     }

writes:

1+2*
3/(4+5)
*2


namespace Delimiter { class Program { static void Main(string[] args) { string src = "a{b{c{d,e}f}g}h"; int occurenceCount = 0; foreach (char ch in src) { if(ch == '{') { occurenceCount++; } } Console.WriteLine("Enter a no. to remove block: "); int givenValue = 0; CheckValid(out givenValue);

        int removeCount = occurenceCount + 1 - givenValue;
        occurenceCount = 0;
        int startPos = 0;
        for (int i = 0; i < src.Length; i++)
        {
            if (src[i] == '{')
            {
                occurenceCount++;
            }   
            if(occurenceCount == removeCount)
            {
                startPos = i;
                break;
                //i value { of to be removed block
            }
        }
        int endPos = src.IndexOf('}', startPos);
        src = src.Remove(startPos,endPos);

        //index of }
        Console.WriteLine("after reved vale:" + src);
        Console.ReadKey();
    }

    public static void CheckValid(out int givenValue)
    {
        if (!int.TryParse(Console.ReadLine(), out givenValue))
        {
            Console.WriteLine("Enter a valid no. to remove block: ");
            CheckValid(out givenValue);
        }
    }
}

}

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