How to remove illegal characters from path and filenames?

Question

I need a robust and simple way to remove illegal path and file characters from a simple string. I\'ve used the below code but it doesn\'t seem to do anything, what am I miss

Answer 1

Here is a function which replaces all illegal characters in a file name by a replacement character:

public static string ReplaceIllegalFileChars(string FileNameWithoutPath, char ReplacementChar)
{
  const string IllegalFileChars = "*?/\\:<>|\"";
  StringBuilder sb = new StringBuilder(FileNameWithoutPath.Length);
  char c;

  for (int i = 0; i < FileNameWithoutPath.Length; i++)
  {
    c = FileNameWithoutPath[i];
    if (IllegalFileChars.IndexOf(c) >= 0)
    {
      c = ReplacementChar;
    }
    sb.Append(c);
  }
  return (sb.ToString());
}

For example the underscore can be used as a replacement character:

NewFileName = ReplaceIllegalFileChars(FileName, '_');