Question

I’m kind of stuck with this pretty simple (I’m sure) jQuery/Javascript issue.
Here’s the code :

jQuery.validator.addMethod("emailExists", function(value, element, param) {
var email = value || '';
var valid = 0;
$.ajax({
  type: "POST",
  url: param,
  data: "email=" + email,
  success: function(msg) {
                if (msg != '' && msg)
                {
                    valid = 0;
                }
                else
                {
                    valid = 1;
                }
        }
});
return valid;
}, "* Email address already registered, please login.");

This function is called where a user type his email address in a registration form, and everything seems to work perfectly, except that my valid variable returned isn’t updated, whereas when I use an alert box it is properly done!

It looks like it return the value before the AJAX is done, any idea?

Cheers,
Nicolas.

Answer 1

Your code fails, because ajax works asynchronously. your return statement is reached before the success function is called. To make it synchronous add async: false to your ajax call like this:

$.ajaxA({
  async: false,
  type: "POST",
  url: param,
  data: "email=" + email,
  success: function(msg) {
                if (msg != '' && msg)
                {
                    valid = 0;
                }
                else
                {
                    valid = 1;
                }
        }
});