Confused on jquery .ajax .done() function

Question

I\'m a bit confused on how to use the ajax .done() function. I\'m working on validating a form to check if a user exists in database and though ajax would be the best approach (

Answer 1

On your php side, you should echo some json string, for example I'll do like this on the validateUser.php :

//Check your database etc.
$user_exists = array('error'=>false,'user'=>true);
echo json_encode($user_exists);

And than with jQuery :

$.ajax({
    url: "validateUser.php",
    type: "post",
    data: "username= " + username,
    dataType: "json",
  }).done(function(result){
    if (result.error == false){
        //No errors, check user
        if(result.user == true)
            alert("Exists"); //now do some stuff
        else
            alert("User don't exists");
    }else{
      // There is an error
    }
  });