范围在$就回调函数(Scope in an $.ajax callback function)

如果我使用这段代码为什么范围变更为“doStuff”警报？ 有没有一种方法，我可以保证的范围是我的对象，而不是Window对象？

下面是相同的代码的jsfiddle 。

(function ($) {
    var c$ = {};

    c$.TestScope = function () {

        this.doAjax = function (onComplete) {
            var self = this;
            $.ajax({
                url: 'badurl',
                complete: function (data) {
                    alert('doAjax2 self === c$.oTestScope: ' + (self === c$.oTestScope).toString());
                    onComplete(data);
                }
            });
            alert('doAjax1 self === c$.oTestScope: ' + (self === c$.oTestScope).toString());  
        };

        this.doStuff = function (data) {
            var self = this;
            alert('doStuff self === c$.oTestScope: ' + (self === c$.oTestScope).toString());
        }

    };

    c$.oTestScope = new c$.TestScope();
    c$.oTestScope.doAjax(c$.oTestScope.doStuff);
})(jQuery);​

Answer 1:

你应该可以指定this在你的价值作为上下文$.ajax()的参数：

var c$ = {};

c$.TestScope = function() {

    this.doAjax = function(onComplete) {

        alert('doAjax1 this === c$.oTestScope: ' + (this === c$.oTestScope).toString());

        $.ajax({
            url: 'badurl',
            context: this,
            complete: function(data) {
                alert('doAjax2 this === c$.oTestScope: ' + (this === c$.oTestScope).toString());
                onComplete.call(this, data);
            }
        });
    };

    this.doStuff = function(data) {
        alert('doStuff this === c$.oTestScope: ' + (this === c$.oTestScope).toString());
    }

};

c$.oTestScope = new c$.TestScope();
c$.oTestScope.doAjax(c$.oTestScope.doStuff);

编辑我做了一个小提琴 ，这和验证其工作正常。 有没有乱搞一个额外的self参数或有渣土周围的封锁，让您的变量。

你失踪哪一部分被调用onComplete.call(this, data)来调用doStuff()

Answer 2:

我已经改变了你的代码的引用传递this到doStuff（）代码。

(function ($) {
    var c$ = {};

    c$.TestScope = function () {

        this.doAjax = function (onComplete) {
            var self = this;
            $.ajax({
                url: 'badurl',
                complete: function (data) {
                    alert('doAjax2 self === c$.oTestScope: ' + (self === c$.oTestScope).toString());
                    onComplete(data,self);
                }
            });
            alert('doAjax1 self === c$.oTestScope: ' + (self === c$.oTestScope).toString());  
        };

        this.doStuff = function (data,thisRef) {
            var self = thisRef;
            alert('doStuff self === c$.oTestScope: ' + (self === c$.oTestScope).toString());
        }

    };

    c$.oTestScope = new c$.TestScope();
    c$.oTestScope.doAjax(c$.oTestScope.doStuff);
})(jQuery);​

文章来源: Scope in an $.ajax callback function