ajax - 获取函数外部json请求的变量(jquery)

Question

我觉得问这个问题很愚蠢，但是我怎样才能在函数之外获取变量 crdnts

$(function() {
    var coordinates = {
        LoadDefault: function() {
             $.getJSON('http://api.wipmania.com/jsonp?callback=?', '', function(json) {
                var crdnts = json.latitude + "," + json.longitude;
                //alert(crdnts);//this works
                return crdnts;
            });
        }
    };
    alert(coordinates.LoadDefault());//I would like to get the crdnts variable here.
});

或

http://jsfiddle.net/stofke/Lv3YD/

Answer 1

javascript ajax 是异步的。所以你需要使用回调:

$(function() {
    var coordinates = {
        LoadDefault: function() {
             $.getJSON('http://api.wipmania.com/jsonp?callback=?', '', function(json) {
                var crdnts = json.latitude + "," + json.longitude;
                call_alert(crdnts); //callback
            });
        }
    };
    function call_alert(cr){
         alert(cr);
    }
    coordinates.LoadDefault();
});