Question

Imagine the first time, the data doesn’t matched and ajax has returned the request then sending an error message to the form, after that how do i stop ajax call if there’s no changes made on the form/input?

$("input[name=signup]").click(function(event) {

if ($(this).attr('type') == "submit" && $(this).attr('name') == "signup") {

        formValidate = function() {
            $.ajax({
                url:   "/ajax/req-signup.aspx",
                type: "post",
                dataType: "json",
                data: { ... },
                success: function(response) { ... }
            });
        }
        formValidate();
    }
event.preventDefault();
});

Answer 1

add a global variable

var allowAjax = true;

set it to false when validation fails:

allowAjax = false;

set to true when changing something in the form

$("input").change(function () {
    allowAjax = true;
});

and check it’s status when making the ajax call:

if ($(this).attr('type') == "submit" 
   && $(this).attr('name') == "signup" 
   && allowAjax ) { ... }

Alternatively, you can disable the submit button when the validation fails and enable it on change.

$(":submit").attr('disabled', 'disabled');

If you don’t mind using a plugin, check out jQuery disabler widget, you might find it easier to use.