对象内部的回调

Question

Why doesn't this work

I have an ajax function via jquery inside an object, and for some reason it's not seeing the other functions in the object inside the callback function.

function object () {

this.test = function () { alert ("test") }

this.makeQuery = function() {
$.ajax( { 
    url: stuff,
    dataType: "xml",
    success: function (data) {  makeData(data) } } )        

}   

this.makeData = function (data) {

  this.test();   // Error "this.test() is not a function"
}

}

Answer 1

The reason is because callback functions are called with a different "this". In the case of the jQuery.ajax call, the "this" function is the jqXHR object http://api.jquery.com/Types/#jqXHR. So if you want to pass the "this" object into the callback you must capture it in the scope and the reference the captured variable. Like this (if I fix all your syntax errors):

function myFunction() {
    var that = this;
    this.test = function () { alert ("test") };

    this.makeQuery = function() {
        jQuery.ajax({
                type: 'post',
                url: 'someUrl',
                dataType: 'json',
                success: function (data, textStatus, jqXHR) {
                    that.makeData(data);
                },
                error: function (jqXHR, textStatus, textError) {
                }
            });
        };

    this.makeData = function(data) {
        this.data = data
        this.test();   // Error "this.test() is not a function"
    };
}
var m = new myFunction();
m.makeQuery();