js下用gb2312编码解码实现方法

function encodeToGb2312(str){
var strOut="";
for(var i = 0; i < str.length; i++){
var c = str.charAt(i);
var code = str.charCodeAt(i);
if(c==" ") strOut +="+";
else if(code >= 19968 && code <= 40869){
index = code - 19968;
strOut += "%" + z.substr(index*4,2) + "%" + z.substr(index*4+2,2);
}
else{
strOut += "%" + str.charCodeAt(i).toString(16);
}
}
return strOut;
}
function decodeFromGb2312(str){
var strOut = '';
for (var i=0;i<str.length; i++){
var c = str.charAt(i);
// +是空格
if (c == '+'){
strOut += ' ';
}
// a,b,c,1,2等，非%开头的，直接返回本身
else if (c != '%'){
strOut += c;
}
// %开头
else{
i++;
var nextC = str.charAt(i);
// 数字，则不是汉字
if (!isNaN(parseInt(nextC))){
i++;
strOut += decodeURIComponent(c+nextC+str.charAt(i));
}
else{
var x = new String();
try
{
var code = str.substr(i,2)+str.substr(i+3,2);
i = i + 4;
var index = -1;
while ((index = z.indexOf(code,index+1)) != -1){
if (index%4 == 0){
strOut += String.fromCharCode(index/4+19968);
break;
}
}
}catch(e){}
}
}
}
return strOut;
}
var z='{0}';

StringBuilder sb = new StringBuilder();
string strFormat = @"...z = '"; // 前面的js代码
const int MinHanzi = 19968;
const int MaxHanzi = 40869;
for (int i = MinHanzi; i < MaxHanzi + 1; i++)
{
byte[] bytes = Encoding.GetEncoding("gb2312").GetBytes(((char)i).ToString());
sb.AppendFormat("{0}{1}", Convert.ToString(bytes[0], 16).ToUpper(), Convert.ToString(bytes[1], 16).ToUpper());
}
string str = strFormat + sb.ToString(0, sb.Length - 1) + "';";
System.IO.File.WriteAllText(@"F:\encodeGb2312.js", str, Encoding.ASCII);