How to wait for ajax validation to complete before submitting a form?

Question

Having a problem where the form submits before the validateUsername function has a chance to complete the username check on the server-side.

How do I submit the form

Answer 1

In jQuery there is a solution for the same. I need to check if a user exists or not in my application during some JavaScript. Here is the code:

var pars = "username="+ username;
var some = $.ajax({url: 'AjaxUserNameExist.php',
  type: 'GET',
  data: pars,
  async: false
}).responseText;


if(some=="1") //this is value Got from PHP
{
  alert("We cannot Go");
  return false;
}

if(some=="0")
{
  alert("We can Go");
  return true;
}