Question

i have a following type of string format —

Proposal is given to {Jwala Vora#3/13} for {Amazon Vally#2/11} {1#3/75} by {MdOffice employee#1/1}

the string contains pair of { } with different positions and may be n number of times.
now i want to replace that pair with other strings which i will compute depending on the string between { } pair.

how to do this ?

Answer 1

You could try regular expressions. Specifically, Regex.Replace variants using MatchEvaluator should do the trick. See http://msdn.microsoft.com/en-US/library/cft8645c(v=vs.80).aspx for more information.

Something along these lines:

using System;
using System.Text.RegularExpressions;

public class Replacer
{
    public string Replace(string input)
    {
        // The regular expression passed as the second argument to the Replace method
        // matches strings in the format "{value0#value1/value2}", i.e. three strings
        // separated by "#" and "/" all surrounded by braces.
        var result = Regex.Replace(
            input,
            @"{(?<value0>[^#]+)#(?<value1>[^/]+)/(?<value2>[^}]+)}",
            ReplaceMatchEvaluator);
        return result;
    }

    private string ReplaceMatchEvaluator(Match m)
    {
        // m.Value contains the matched string including the braces.
        // This method is invoked once per matching portion of the input string.
        // We can then extract each of the named groups in order to access the
        // substrings of each matching portion as follows:
        var value0 = m.Groups["value0"].Value; // Contains first value, e.g. "Jwala Vora"
        var value1 = m.Groups["value1"].Value; // Contains second value, e.g. "3"
        var value2 = m.Groups["value2"].Value; // Contains third value, e.g. "13"

        // Here we can do things like convert value1 and value2 to integers...
        var intValue1 = Int32.Parse(value1);
        var intValue2 = Int32.Parse(value2);

        // etc.

        // Here we return the value with which the matching portion is replaced.
        // This would be some function of value0, value1 and value2 as well as
        // any other data in the Replacer class.
        return "xyz";
    }
}

public static class Program
{
    public static void Main(string[] args)
    {
        var replacer = new Replacer();
        var result = replacer.Replace("Proposal is given to {Jwala Vora#3/13} for {Amazon Vally#2/11} {1#3/75} by {MdOffice employee#1/1}");
        Console.WriteLine(result);
    }
}

This program will output Proposal is given to xyz for xyz xyz by xyz.

You’ll need to provide your app-specific logic in the ReplaceMatchEvaluator method to process value0, value1 and value2 as appropriate. The class Replacer can contain additional members that can be used to implement the replacement logic in ReplaceMatchEvaluator. Strings are processed by calling Replace on an instance of the Replacer class.