如何处理包含其他JavaScript对象的JavaScript对象中的“ this”？
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我正在使用John Resig的出色javascript类来实现简单的javascript继承，并且我不禁烦恼一些与\'this \'关键字有关的变量范围问题。
我的延伸课程看起来像这样
var EUNode = Class.extend({
// Methods
//-------------------------------------------------------------------------------
init : function(){
this.div = this.createDiv();
this.canDoStuff = true;
this.div.addEventListener(touchstart, this.touchStartHandler, false);
},
// Create Div
//-------------------------------------------------------------------------------
createDiv : function(){
// code to create a DIV element, add some classes and do some
// other useful stuff
},
touchStartHandler : function(event){
// In here, \'this\' refers to the div element, so the
// following condition doesn\'t work
if(this.canDoStuff){
// do some stuff
}
}
});
var EUNode = Class.extend({
// Methods
//-------------------------------------------------------------------------------
init : function(){
this._super();
// Store a reference to \'this\' globally
self = this;
self.div = this.createDiv();
self.canDoStuff = true;
self.div.addEventListener(touchstart, self.touchStartHandler, false);
},
touchStartHandler : function(event){
if(self.canDoStuff){
// Now I can do stuff, but \'self\' is now a global variable
// which isn\'t what I want. If there\'s more than one instance
// of EUNode, \'self\' references the newest instance.
}
}
});
没有找到相关结果
已邀请:
4 个回复
钨蜡唤喉晤
。 您还使依赖于某些全局变量，并且此函数的整体工作可能不再那么清楚。 只需在适当的上下文中致电：init : function(){ var self = this; // <- local `self` this.div = this.createDiv(); this.canDoStuff = true; // pass a closure, making `self` available inside the function this.div.addEventListener(touchstart, function(event) { self.touchStartHandler(event); }, false); },[docs]（请参阅其他浏览器的实现链接）来绑定元素，这应参考：逝媳蘑贩茄
var boundHandler = function(event) { yourInstance.touchStartHandler(event); };舶啥戚
尝试self.div.addEventListener(touchstart, function(event) { self.touchStartHandler(event) }, false);淘圃跺枯替