AJAX對象IE 8錯誤

Question

隨着代碼下面，我得到錯誤：

消息：未實現。 Line：this.xmlHttpRequestObject.onreadystatechange = onreadystatechange;

ajax.js

function Ajax(url, method, onreadystatechange, asynchronous) { 
    this.xmlHttpRequestObject = new XMLHttpRequest(); 
    this.method = method; 
    this.url = url; 
    this.asynchronous = asynchronous === undefined ? true : asynchronous; 
    this.xmlHttpRequestObject.onreadystatechange = onreadystatechange; 
} 

Ajax.prototype.send = function() { 
    this.xmlHttpRequestObject.open(this.method, this.url, this.asynchronous); 
    this.xmlHttpRequestObject.setRequestHeader('X-Requested-With', 'XMLHttpRequest'); 
    this.xmlHttpRequestObject.send(); 

    return this; 
}; 

Ajax.prototype.onreadystatechange = function (onreadystatechange) { 
    this.xmlHttpRequestObject.onreadystatechange = onreadystatechange; 

    return this; 
}; 

Ajax.prototype.onloadstart = function (onloadstart) { 
    this.xmlHttpRequestObject.onloadstart = onloadstart; 

    return this; 
}; 

Ajax.prototype.onload = function (onload) { 
    this.xmlHttpRequestObject.onload = onload; 

    return this; 
}; 

scripts.js中

function loadPage(page) { 
    var ajax = new Ajax(page, 'GET'); 

    ajax.onloadstart(function() { 
     var div = document.createElement('div'), 
      p = document.createElement('p'), 
      img = document.createElement('img'), 
      section = document.querySelector('section'); 

     removeChildrenElements(section); 
     section.style.minHeight = '230px'; 

     div.setAttribute('id', 'loading'); 

     img.setAttribute('src', 'media/images/loading.gif'); 
     img.setAttribute('alt', 'Carregando'); 

     p.appendChild(document.createTextNode('Carregando. Por favor, aguarde ...')); 

     div.appendChild(p); 
     div.appendChild(img); 

     document.querySelector('section').appendChild(div); 
    }); 

    ajax.onreadystatechange(function (event) { 
     if (this.readyState === 4 && this.status === 200) { 
      document.querySelector('section').innerHTML = this.responseText; 
     } else if (this.status === 404) { 
      this.abort(); 
      document.location = 'http://www.mydomain.com.br/404'; 
     } 
    }); 

    ajax.send(); 
} 

這個腳本在Firefox 4，谷歌Chrome和Opera的作品。 謝謝。

Answer 1

可能是與窗口/文檔對象衝突。嘗試將代碼更改爲

Ajax.prototype.onreadystatechange = function (readystatechange) { 
    this.xmlHttpRequestObject.onreadystatechange = readystatechange; 
    return this; 
};