How can i add a method to mscorelib

Hi. I want to add some methods to mscorlib. For example:

string abc;

abc.IsNumeric()

i hope could explain my question.

From stackoverflow cagin

• You can't add methods to mscorlib, however you can use extension methods so they appear as if they are defined on string, e.g.

  public static class StringExtensions
  {
      public static bool IsNumeric(this string s)
      {
          // TODO
      }
  }
  

  Which you can then call as you requested, e.g.

  "1234".IsNumeric()
  

  From Greg Beech

• You got a good answer by Greg. Just wanted to add that you can read more about extension methods here:

  • Extension Methods (C# Programming Guide)
  • Extension Methods (Visual Basic)
  From Fredrik Mörk