Question

Why doesn’t this work?

var myData;

function getData()
{
    $.ajax(
        { 
            url: dataURL, 
            success: function(data)
            {
                myData = data;
            }
        }
    );
}

getData();
console.log(myData);

I’m scoping the variable correctly, but I can’t use the data outside the function..

Answer 1

AJAX is asynchronous. It runs in the background while you code is running. So, when you’re calling console.log(myData);, the AJAX call isn’t done yet, so the variable isn’t set.

You should use the callback function to process the data, like so:

function getData(){
    $.ajax({ 
        url: dataURL, 
        success: function(data){
            console.log(data);
        }
    });
}

getData();