How do I return a value from ajax call in jQuery?

Question

Look at my code:

function dialogTexts() {
    var langText = $.ajax({
        type: 'GET',
        url: '/main/getdialogtexts',
        dataType: 'json'
    });

    langText.done(function(data) {  
        //data contains a array returned correctly from php            

        //The data.delete is returned correctly from php. data.delete contains a string 
        return data.delete; 
    });                        

    langText.fail(function(ts) {
        alert(ts.responseText);
    });
}

Why does the variable lang get undefined when calling above function?

var lang = dialogTexts();

score 1 · Answer 1 · edited May 23 '17 at 11:57

1

You can't return a value from an asynchronous ajax call. You can only get its value from a callback. Unless you use async:false which is not recommended because it freezes the UI while the request is pending.

See How do I return the response from an asynchronous call?

function dialogTexts(callback) {
    var langText = $.ajax({
        type: 'GET',
        url: '/main/getdialogtexts',
        dataType: 'json'
    });

    langText.done(function(data) {  
        //data contains a array returned correctly from php            
        callback(data.delete)
        //The data.delete is returned correctly from php. data.delete contains a string 
        return data.delete; 
    });                        

    langText.fail(function(ts) {
        callback(false);
    });
}

dialogText(function(text) {
    alert(text);
})

edited May 23 '17 at 11:57

Community

1
1

answered Mar 13 '14 at 20:45

Ruan Mendes

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you mean `async:false` ? – andrew Mar 13 '14 at 20:47
Ok, thanks! Maybe I'm tired, but I don't quite understand how to return from the callback - function. I've tried to use a return inside the dialogTexts(function(text)) and then try var lang = dialogTexts() but of course that won't work. Your code works, but I want to store the returnvalue of callback into a variable. – bestprogrammerintheworld Mar 13 '14 at 21:05
@bestprogrammerintheworld See how you have two inner functions? You added return values for one of them but `dialogTexts` is not returning anything. Even if you tried to set a variable that you returned in `dialogTexts` from the inner handler, `dialogText` will have already returned by the time the callback is called and would have returned the value before the variable was set. – Ruan Mendes Mar 14 '14 at 01:48

How do I return a value from ajax call in jQuery?

1 Answers1