Count regex replaces (C#)

Question

Is there a way to count the number of replacements a Regex.Replace call makes?

E.g. for Regex.Replace(\"aaa\", \"a\", \"b\"); I want to get the number 3

Answer 1

This should do it.

     int count = 0;
     string text = Regex.Replace(text,
          @"(((http|ftp|https):\/\/|www\.)[\w\-_]+(\.[\w\-_]+)+([\w\-\.,@?^=%&:/~\+#]*[\w\-\@?^=%&/~\+#])?)", //Example expression. This one captures URLs.
          match =>
          {
               string replacementValue = String.Format("{0}", match.Value);
               count++;
               return replacementValue;
          });

I am not on my dev computer so I can't do it right now, but I am going to experiment later and see if there is a way to do this with lambda expressions instead of declaring the method IncrementCount() just to increment an int.

EDIT modified to use a lambda expression instead of declaring another method.

EDIT2 If you don't know the pattern in advance, you can still get all the groupings (The $ groups you refer to) within the match object as they are included as a GroupCollection. Like so:

     int count = 0;
     string text = Regex.Replace(text,
          @"(((http|ftp|https):\/\/|www\.)[\w\-_]+(\.[\w\-_]+)+([\w\-\.,@?^=%&:/~\+#]*[\w\-\@?^=%&/~\+#])?)", //Example expression. This one captures URLs.
          match =>
          {
               string replacementValue = String.Format("{0}", match.Value);
               count++;
               foreach (Group g in match.Groups)
               {
                    g.Value; //Do stuff with g.Value
               }
               return replacementValue;
          });