jQuery AJAX not returning false

Question

I want my program below to return false if the employee ID exists. My PHP file echoes true if the employee ID exists and it is returned to the AJAX function.

$.post("connect_ajax_php.php",
    {type: "checkId", val: val, field: "emp_id", table: "employee"})
    .done(function(data, succ){
        data = $.trim(data);
        if( succ =="success" && data=="true" ){
            $( errContId ).html( val+" already exist" );
            $( id ).css( {"border":"1px solid red"} );
            $('#'+sucImg).html("<img src='images/background/error.png'>");
            return false;
        }else{
            $( errContId ).html("");
            $( id ).css( {"border":"1px solid #ccc"} );
            $('#'+sucImg).html("<img src='images/background/success.png'>");
        }
    });

You cannot return a value from an asynchronous call that way. Please review http://stackoverflow.com/questions/14220321/how-to-return-the-response-from-an-asynchronous-call. — Jasen, Jul 24 '15 at 02:15
Nope, you are not able to return anything in AJAX.. refer to @Jasen link — choz, Jul 24 '15 at 02:27
what I want is: I don't want the form to be submitted if php file echos true so that jquery ajax will return false to prevent the form been submitted, meaning that that employee Id already exist. thanks — TETENGIOUS, Jul 24 '15 at 09:01
how can I also turn asynchronous to be false as async: false in my code above. — TETENGIOUS, Jul 24 '15 at 09:10
how can I also turn asynchronous to be false as async: false in my code above. — TETENGIOUS, Jul 24 '15 at 09:20

score 0 · Answer 1 · answered Jul 24 '15 at 17:51

If you are using the ajax call as a validation step you will manually submit the form in the ajax callback. Then move the return false to the click handler rather than call it from the ajax response handler.

<form id="myform" action="/url" method="post">
    ...
    <button id="submitbtn" type="submit">Submit</button>
</form>

$("#submitbtn").on("click", function(event) {
    $.ajax({
        url: "connect_ajax_php.php",
        method: "post",
        data: {type: "checkId", val: val, field: "emp_id", table: "employee"}
    })
    .done(function(result) {
        if (result == "true") {
            // id exists
        }
        else {
            $("#myform").submit();
        }
    });

    return false;  // prevent standard form submission
});

jQuery AJAX not returning false

1 Answers1