The SwapCase function turns lowercase characters into uppercase and uppercase characters into lowercase.

1. <script type=“text/javascript”>
2. String.prototype.SwapCase = function()
3. {
4.  return this.replace(/([a-z])|([A-Z])/g,
5.  function($0,$1,$2)
6.  {
7.  return ($1) ? $0.toUpperCase() : $0.toLowerCase()
8.  })
9. }
10. </script>
12. <script type=“text/javascript”>
13. alert(“No Country For Old Men”.SwapCase()); // Returns “nO cOUNTRY fOR oLD mEN”
14. </script>