String.Replace() will not change the source string of the variable

Question

I have the following code inside my c# application:-

 string[] excludechar = { "|", "\\", "\"", "'", "/", "[", " ]", ":", "<", " >", "+", "=", ",", ";", "?", "*", " @" };
 var currentgroupname = curItemSiteName;
 for (int i = 0; i < excludechar.Length; i++)
       {
         if (currentgroupname.Contains(excludechar[i]))
             currentgroupname.Replace(excludechar[i], "");       
       }
 site.RootWeb.SiteGroups.Add(currentgroupname)

now in my abive code the currentgroupname variable which i am passing inside the .ADD function will have all the special characters i have replaced inside my for loop. so can anyone adivce if i can modify my code so the .Replace will be actually replacing the original string of the currentgroupname ...

maybe currentgroupname = currentgroupname.Replace(excludechar[i], ""); — Esteban Verbel, Jan 16 '17 at 18:06
`currentgroupname = currentgroupname.Replace(...);` As always, check the [documentation](https://msdn.microsoft.com/en-us/library/fk49wtc1(v=vs.110).aspx). — Michael McGriff, Jan 16 '17 at 18:06
strings are immutable. You'll just be creating a new string, and replacing your old string with the new one (following ^) — Steve's a D, Jan 16 '17 at 18:07

score 2 · Answer 1 · answered Jan 16 '17 at 18:08

You are not actually assigning the "replaced" string to currentgroupname

 string[] excludechar = { "|", "\\", "\"", "'", "/", "[", " ]", ":", "<", " >", "+", "=", ",", ";", "?", "*", " @" };
 var currentgroupname = curItemSiteName;
 for (int i = 0; i < excludechar.Length; i++)
       {
         if (currentgroupname.Contains(excludechar[i]))
             currentgroupname = currentgroupname.Replace(excludechar[i], "");       
       }
 site.RootWeb.SiteGroups.Add(currentgroupname)

score 0 · Answer 2 · answered Jan 16 '17 at 18:17

0

Isn't it easier with some regex?

var input = "<>+--!I/have:many@invalid\\|\\characters";
var result = Regex.Replace(input, @"\W", "");
Console.Write(result); //Ihavemanyinvalidcharacters

Don't forget the using:

using System.Text.RegularExpressions;

answered Jan 16 '17 at 18:17

Luis Lavieri

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String.Replace() will not change the source string of the variable

2 Answers2