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How to check a regular expression string is valid or not?

tunhien asked
Last Modified: 2008-03-10
I try to write a program that allow people to input an regular expression and then I will use it to excute. But If the input string is not a valide regular expression then when execute it, the executer will through error.
It's not good. And I wanna check the valide of it!

So please show me how to do that!
Thanks so much!
Watch Question

Maybe there is an easier way....  try using a  "try .. catch..."  block when you create the regex object:

try {

var re = new RegExp(document.yourFormName.regexTextBox.value);
catch {
  alert("that's some funky regex dude.");
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