给moz-firefox下添加IE方法和属性

            return this.parentNode.replaceChild(range.extractContents(),this);
            }
        }
    Node.prototype.swapNode=function(Node){// 交换节点
        var nextSibling=this.nextSibling;
        var parentNode=this.parentNode;
        node.parentNode.replaceChild(this,Node);
        parentNode.insertBefore(node,nextSibling);
        }
    }
if(window.HTMLElement){
    HTMLElement.prototype.__defineGetter__("all",function(){
        var a=this.getElementsByTagName("*");
        var node=this;
        a.tags=function(sTagName){
            return node.getElementsByTagName(sTagName);
            }
        return a;
        });
    HTMLElement.prototype.__defineGetter__("parentElement",function(){
        if(this.parentNode==this.ownerDocument)return null;
        return this.parentNode;
        });
    HTMLElement.prototype.__defineGetter__("children",function(){
        var tmp=[];
        var j=0;
        var n;
        for(var i=0;i<this.childNodes.length;i++){
            n=this.childNodes[i];
            if(n.nodeType==1){
                tmp[j++]=n;
                if(n.name){
                    if(!tmp[n.name])
                        tmp[n.name]=[];
                    tmp[n.name][tmp[n.name].length]=n;