//兼容firefox的outerHTML属性
if (window.HTMLElement) {
  HTMLElement.prototype.__defineSetter__("outerHTML",function(sHTML) {
        var r=this.ownerDocument.createRange();
        r.setStartBefore(this);
        var df=r.createContextualFragment(sHTML);
        this.parentNode.replaceChild(df,this);
        return sHTML;
    });

    HTMLElement.prototype.__defineGetter__("outerHTML",function() {
     var attr;
        var attrs=this.attributes;
        var str="<"+this.tagName.toLowerCase();
        for (var i=0;i<attrs.length;i++) {
            attr=attrs[i];
            if(attr.specified)
                str+=" "+attr.name+'="'+attr.value+'"';
        }
        if(!this.canHaveChildren)
            return str+">";
        return str+">"+this.innerHTML+"</"+this.tagName.toLowerCase()+">";
        });

   HTMLElement.prototype.__defineGetter__("canHaveChildren",function() {
     switch(this.tagName.toLowerCase()) {
         case "area":
         case "base":
         case "basefont":
         case "col":
         case "frame":
         case "hr":
         case "img":
         case "br":
         case "input":
         case "isindex":
         case "link":
         case "meta":
         case "param":
         return false;
     }
     return true;
   });
}