C# How to get and display text content from windows clipboard

using System;
using ;
namespace RobvanderWoude
{
 class Paste
 {
  [STAThread]
  static int Main( string[] args )
  {
   if (  == 0 )
   {
    try
    {
     if ( ( ) )
     {
      string clipText = ( );
      ( clipText );
      return 0;
     }
     else
     {
      return 1;
     }
    }
    catch ( Exception e )
    {
     (  );
     return 2;
    }
   }
   else
   {
    ( );
    ( ", Version 1.01" );
    ( "Read and display text from the clipboard" );
    ( );
    ( "Usage: PASTE" );
    ( );
    ( "Note:  The program returns the following 'errorlevels':" );
    ( " 0 success" );
    ( " 1 no text available in clipboard" );
    ( " 2 command line or unknown error" );
    ( );
    ( "Written by Rob van der Woude" );
    return 2;
   }
  }
 }
}