关于在文本框中输入HTML的处理

Question

<script language="JavaScript">
<!--
String.prototype.EncodeHTML=function()
{
var str=this;
str=str.replace(/\x26/g,"&#38;");
str=str.replace(/\x3c/g,"&#60;");
str=str.replace(/\x3e/g,"&#62;");
str=str.replace(/\x22/g,"&#34;");
str=str.replace(/\x27/g,"&#39;");
return str;
}
//-->
</script>
<input name=txt><input type=button onclick="alert(txt.value.EncodeHTML());test.innerHTML=txt.value.EncodeHTML()" value="go">
<span id=test></span>

Answer 1

sorry,忘了还有空格
加上str=str.replace(/\x10/g,"&#160");

Answer 2

又错了,:(
str=str.replace(/\x20/g,"&#160;");

Answer 3

还有就是限制不让输入<> &等一些字符