Shree Shree - 3 months ago 24
ASP.NET (C#) Question

Replace the last occurence of a word in a string - c#

I have a problem where I need to replace the last occurrence of a word in a string.

Situation: I am given a string which is in this format:

string filePath ="F:/jan11/MFrame/Templates/feb11";


I then replace
TnaName
like this:

filePath = filePath.Replace(TnaName, ""); //feb11 is TnaName


This works, but I have a problem when
TnaName
is the same as my
folder name
. When this happens I end up getting a string like this:

F:/feb11/MFrame/Templates/feb11


Now it has replaced both occurences of
TnaName
with
feb11
. Is there a way that I can replace only the last occurence of the word in my string? Thanks.

Note:
feb11
is
TnaName
which comes from another process - that's not a problem.

Answer

Here is the function to replace the last occurrence of a string

public static string ReplaceLastOccurrence(string Source, string Find, string Replace)
{
        int place = Source.LastIndexOf(Find);

        if(place == -1)
           return Source;

        string result = Source.Remove(place, Find.Length).Insert(place, Replace);
        return result;
}
  • Source is the string on which you want to do the operation.
  • Find is the string that you want to replace.
  • Replace is the string that you want to replace it with.
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