全球範圍 - 訪問「這個」射擊事件偵聽器

Question

後，我有一個MooTools的類，使用XHR上傳文件：

var foo = new Class({ 

    initialize: function() { 

     this.bar = 'value'; 
    }, 

    upload: function() { 

     // This method uploads a file 

     …. 
     xhr.addEventListener('load', this.uploadComplete, false); 
     …. 

    }, 
    uploadComplete: function() { 

     // Is getting called on completion of file upload  

     console.log(this.bar); // undefined, but I want to to be 'value' 
    } 


}); 

我想訪問this.bar在uploadComplete方法，但this是沒有得到穿過在xhr.addEventListener('load', this.uploadComplete, false);

任何幫助表示讚賞。

Answer 1

您需要使用Function.prototype.bind - https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/bind和http://mootools.net/docs/core/Types/Function#Function:bind - 當事件觸發時，它將正確設置上下文。

xhr.addEventListener('load', this.uploadComplete.bind(this), false);