RegEx javascript not matching correctly -

i have small javascript funtcion :

function getfilteredlistlimited(event) {     var $source = $(event.target);     var $pattern = event.data.pattern;     var re = new regexp($pattern, 'i');     if (re.test($source.val())) {         console.log('regex match');     } }; 

the pattern used is:

^[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,4}$ 

which should match email-addresses.

using http://regexpal.com/ can see pattern correct. weird reason script matches @ 4th character after @

abc@abcd should not give match, does. suggestions ?

you need aware of regexp constructor escaped characters must double-escaped. so, regex string passed regexp constructor should like:

^[a-z0-9._%+-]+@[a-z0-9.-]+\\.[a-z]{2,4}$ 

the fix can introduced this:

var re = new regexp($pattern.replace(/\\/g, '\\\\'), 'i'); 

it work if escape symbols used consistently.