JavaScript 扩展 String 对象实现 HTML 编码与解码

String.prototype.HTMLEncode = function() {
var temp = document.createElement("div");
(temp.textContent != null) ? (temp.textContent = this) : (temp.innerText = this);
var output = temp.innerHTML;
temp = null;
return output;
} 
String.prototype.HTMLDecode = function() {
var temp = document.createElement("div");
temp.innerHTML = this;
var output = temp.innerText || temp.textContent;
temp = null;
return output;
}