How to replace space/character with specified character after first numeric value in string using C#? -

i have string containing special characters & numeric values .

eg: 3-3 3  3-3"3/4 3-3-3/4 3-3 3/4 3 3 3 3'3 3  output must be:     3f3 3      3f3"3/4     3f3-3/4     3f3 3/4     3f3 3     3f3 3 

i have tried using :

public static string replacefirst(string text, string search, string replace)         {             int pos = text.indexof(search);             if (pos < 0)             {                 return text;             }             return text.substring(0, pos) + replace + text.substring(pos + search.length);         } 

using above code replaces first occurrence specified character works fine.

eg: 3-3 3 output: 3f3 3 

but 3 3-3 output: 3 3f3 according code correct. want replace space/character after first numeric 3f3-3

help appreciated!

simple loops should work.

for(int =0; < mylistofstrings.count; i++) {     char[] chars = mylistofstrings[i].tochararray();     (int j = 0; j < chars.count(); j++)     {        if (char.isdigit(chars[j]))        {            if(j + 1 < chars.count())            {               chars[j + 1] = 'f'; //'f' being replacing character               mylistofstrings[i] = new string(chars);            }            break;        }     } } 

output examples

mylistofstrings.add("3-3 3"); mylistofstrings.add("3-3-3/4"); mylistofstrings.add("3 3-3"); mylistofstrings.add("3 3 3");  3f3 3 3f3-3/4 3f3-3 3f3 3 

update comments

for (int = 0; < mylistofstrings.count; i++) {      char[] chars = mylistofstrings[i].tochararray();      (int j = 0; j < chars.count(); j++)      {          if (!char.isdigit(chars[j]))          {              if (j + 1 < chars.count())              {                  chars[j] = 'f'; //'f' being replacing character                  mylistofstrings[i] = new string(chars);              }              break;          }      } }