Question

I have the following javascript code:

<script type="text/javascript"> //javascript starts

 var patt=/[<](\S+).*>(.*)<\/\1>/;
 var str='<a id="test">hi</a> <p></p>';

 alert(str.match(patt));
 alert(patt.exec(str));

</script>

It is expected to find all tags in a html document. So ideally it should return <a id="test">hi</a>, <p></p>.

But it currently returns <a id="test">hi</a>, a ,hi.

Why is this happening?

Also another question, What is the difference between str.match(patt) and patt.exec(str) and which is better to use?

Answer 1

var patt=/[<](\S+).*>(.*)<\/\1>/g;

try to specify the global modifier (or it will stop at the first occurrence found).

About your second question MDN is a good resource:
From https://developer.mozilla.org/en/JavaScript/Reference/Global_Objects/String/match

If the regular expression does not include the g flag, returns the same result as regexp.exec(string). If the regular expression includes the g flag, the method returns an Array containing all matches. If there were no matches, the method returns null.