How to return false to global variable inside Ajax function

Question

How can I pass true or false outside of this Ajax function? I need to return false on something and I cannot do that within Ajax

    var zip = $('#order-zip').val();

var zipvalidated;

$.ajax({
    type: 'POST',
    url: 'checkzip.php',
    data: {post:zip},
    dataType: 'json',
    success: function(data) {

        zipvalidated = true;

        if (data.response !== "success"){

            console.log(data);
            console.log ("sorry, we are not delivering in your area right now");
            zipvalidated = false;


        }
    }
});

console.log (zipvalidated);

if (zipvalidated == false) {
    return false;
}else{
    console.log ("pass!")
}

Does this answer your question? [How do I return the response from an asynchronous call?](https://stackoverflow.com/questions/14220321/how-do-i-return-the-response-from-an-asynchronous-call) — freedomn-m, Sep 30 '20 at 08:17

Jerson · Answer 1 · 2020-11-17T15:50:03.920

1

You can force your request to be syncronous with async: false , but that's not recommended because it will cause the browser to lock up while waiting for results.

You can use callback function instead

const zip = $('#order-zip').val()
var zipvalidated = true

function getZip(zip,callback) {
    $.ajax({
        type: 'POST',
        url: 'checkzip.php',
        data: {post:zip},
        dataType: 'json',
        success: function(data) {
            callback(data)
        }
    })
}

getZip(zip,function(data) {

    if (data.response !== "success"){
        console.log(data);
        console.log ("sorry, we are not delivering in your area right now");
        zipvalidated = false;
    }
})

console.log (zipvalidated)

edited Nov 17 '20 at 15:50

answered Sep 30 '20 at 03:51

Jerson

1,700
2
10
14

This still doesn't work as it won't let me return false outside of the getZip function. – jac Sep 30 '20 at 06:35
console.log (zipvalidated) will always read true, never false, – jac Sep 30 '20 at 06:41
correct, and also why you need to return false? is that wrap with function? – Jerson Sep 30 '20 at 06:49

score 0 · Answer 2 · answered Sep 30 '20 at 03:48

0

Ajax is by default async, So your if statement runs before zipvalidated variable is updated. Use async/await or try setting async: false on your ajax request.

answered Sep 30 '20 at 03:48

Yannick Vermeulen

148
7

not good idea, you can also use callback function instead – Jerson Sep 30 '20 at 03:55
Please don't recommend `async:false` - it's currently deprecated in chrome (and other browsers no doubt, didn't bother checking) and will be removed in the future. – freedomn-m Sep 30 '20 at 08:18

score 0 · Answer 3 · answered Sep 30 '20 at 07:52

Just put the checking in your callback function

$.ajax({
    type: 'POST',
    url: 'checkzip.php',
    data: {post:zip},
    dataType: 'json',
    success: function(data) {

        zipvalidated = true;

        if (data.response !== "success"){

            console.log(data);
            console.log ("sorry, we are not delivering in your area right now");
            zipvalidated = false;
            console.log (zipvalidated);
            if (zipvalidated == false) {
                return false;
            }else{
                console.log ("pass!")
            }

        }
    }
});

How to return false to global variable inside Ajax function

3 Answers3