Question

I want to take and edit a string in-place in a .NET app. I know that StringBuilder allows me to do in-place appends, inserts, and replaces, but it does not allow an easy way of doing stuff like this:

while (script.IndexOf("@Unique", StringComparison.InvariantCultureIgnoreCase) != -1)
{
   int Location = script.IndexOf("@Unique", StringComparison.InvariantCultureIgnoreCase);
   script = script.Remove(Location, 7);
   script = script.Insert(Location, Guid.NewGuid().ToString());
}

As there is no IndexOf in StringBuilder. Does anyone have an effective way to do in-place editing of textual information?

Edit #1:
Changed sample to make more obvious that each ‘replace’ needs to have a different result.

Answer 1

If your code really is this straightforward then why not just use one of the built-in Replace methods, either on string, StringBuilder or Regex?

EDIT FOLLOWING COMMENT…

You can replace each occurrence with a separate value by using one of the overloads of Regex.Replace that takes a MatchEvaluator argument:

string foo = "blah blah @Unique blah @Unique blah blah @Unique blah";

// replace each occurrence of "@Unique" with a separate guid
string bar = Regex.Replace(foo, "@Unique",
    new MatchEvaluator(m => Guid.NewGuid().ToString()),
    RegexOptions.IgnoreCase));