从ajax响应返回数据

Question

I have this function

function get_last(){
                $.ajax({
                        url:'fronta.php?get_last&last=1',
                        success:function(data) {
                                var last = parseInt(data);

                        }

                });
                return last;

}

but when I call it like

var last = get_last();
alert(last);

firebug gives me "last is not defined"

How can I pass this last variable into global scope ?

Answer 1

function get_last(){
    var last;
    $.ajax({
        url:'fronta.php?get_last&last=1',
        async: false,
        success:function(data) {
            last = parseInt(data);
        }
    });
    return last;
}

Move the declaration of the last variable to the parent function, instead of having it in the callback. In JavaScript, inner functions have access to variables declared in their parent, so last = parseInt(data); will update the variable declared in the parent function.

Also note that you will have to run this synchronously, otherwise the function will return before the response is handled.

Also, it may have been a typo when you wrote the question, but there's a random . character at the end of your url:'fronta... line. You need to get rid of that.