diff --git a/lib/xss.js b/lib/xss.js
index ebbe184..d1214f7 100644
--- a/lib/xss.js
+++ b/lib/xss.js
@@ -10,7 +10,22 @@ var parser = require('./parser');
 var parseTag = parser.parseTag;
 var parseAttr = parser.parseAttr;
 var _ = require('./util');
-
+/**
+*转义字符串中的特殊字符
+* by liwu0213
+*/
+function htmlDecode(str){
+		 if (str == null) {
+			 return '';
+		 }
+		  return String(str).
+			replace(/&/g, '&').
+			replace(/&lt;/g, '<').
+			replace(/&gt;/g, '>').
+			replace(/&quot;/g, '"').
+			replace(/&#039;/g, "'")/*.
+			replace(/&nbsp;/g, " ")*/;
+	}
 
 /**
  * 返回值是否为空