Javascript – How to get return value in a function with inside Ajax call – JQuery

ajaxjavascriptjquery

this may sound very easy to few of you, but i am not able to figure out why I am not able to get the return value, even after chceking many posts 🙁

function getMessageCount() {
                    var count;
                    $.ajax({
                        type: "POST",
                        url: "http://localhost:43390" + "/services/DiscussionWidgetService.asmx/GetMessageCount",
                        dataType: "json",
                        contentType: "application/json; charset=utf-8",
                        success: function (data) {                            
                            count = data.d;
                        } //success
                    });
                    return count;
                }

Now if I call var count = getMessageCount();
it gives me undefinted 🙁
while inside the method count is coming correct, i.e. service is working fine.

Best Answer

I agree with the first line by ahren that 'That's because the $.ajax() call is asynchronous.'

you could try adding a setting - async:false which is true by default. This makes the call synchronous.

you can edit your code as :

function getMessageCount() {
                var count;
                $.ajax({
                    type: "POST",
                    url: "http://localhost:43390" + "/services/DiscussionWidgetService.asmx/GetMessageCount",
                    dataType: "json",
                    async:false,
                    contentType: "application/json; charset=utf-8",
                    success: function (data) {                            
                        count = data.d;
                    } //success
                });
                return count;
            }

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Here's what your code would look like if changed as suggested:

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I read this question and implemented the approach that has been stated regarding setting the response HTTP status code to 278 in order to avoid the browser transparently handling the redirects. Even though this worked, I was a little dissatisfied as it is a bit of a hack.

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    data: reqBody,
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Best Answer

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