Jquery or Javascript if a textarea or input field contains a url - Honey Pot

Question

I am getting a bunch of spam on a web form with URLs. There is no reason for a user to submit a url in this form.

I am trying to write a script to push a spam bot to a post url that doesnt exist.

Here is my code that I cannot get to work...

function testcheck() {
    var submitURL = jQuery('#returnUrl')[0].value;
    if( jQuery("textarea#question").contains("http")) {
            $('.validate').attr('action', 'fakesubmission.php');
            window.location.replace(submitURL);
            return false;
        }
}

What I am trying to do with this function is if http is inputted in the field. Then it will submit to fakesubmission.php. I just need help on the if statement.

Thank you in advance!