初学问题。

var Faceye = {   
    version : 1.0,   
/**  
*简单取得httpRequest  
*/  
    httpRequest : function() {   
        var xRequest = null;   
        if (window.XMLHttpRequest) {   
            xRequest = new XMLHttpRequest();   
        } else if (window.ActiveXObject) {   
            xRequest = new ActiveXObject("MsXml2.XmlHttp");   
        }   
        return xRequest;   
    },   
/**  
*简单的加载文件  
*/  
    load : function(src) {   
        var headerDom = document.getElementsByTagName('head').item(0);   
        var jsDom = document.createElement('script');   
        jsDom.type = 'text/javascript';   
        jsDom.scr = src;   
        headerDom.appendChild(jsDom);   
    },   
/**  
*通过ajax方式加载js  
*/  
    ajaxLoad : function(src) {   
        var xRequest = this.httpRequest();   
        xRequest.open('GET',src,true);   
        xRequest.send(null);   
                    var headerDom = document.getElementsByTagName('head')   
                            .item(0);   
                    var jsDom = document.createElement('script');   
                    jsDom.type = 'text/javascript';   
                    jsDom.language='javascript';   
                    jsDom.defer=true;   
                    jsDom.text=xRequest.responseText;   
                    headerDom.appendChild(jsDom);   
           
    }   
};