用JavaScript实现PHP的urlencode与urldecode函数

很多朋友说JavaScript的decodeURI函数也可以实现，但有bug所有呢，下面看下下面的函数，经过测试使用暂时没什么问题，我在之前的文章说过，这个和php的urldecode函数根本不是一回事。下面是我根据高人的代码改写的JavaScript版的urldecode函数，参考的链接在开头提到的文章中有，就不一一列举了。和之前的urlencode函数一样，只实现了utf-8版的。

1、urlencode

使用方法： urlencode(str);

function urlencode(clearString)
{
var output = '';
var x = 0;

clearString = utf16to8(clearString.toString());
var regex = /(^[a-zA-Z0-9-_.]*)/;

while (x < clearString.length)
{
var match = regex.exec(clearString.substr(x));
if (match != null && match.length > 1 && match[1] != '')
{
output += match[1];
x += match[1].length;
}
else
{
if (clearString[x] == ' ')
output += '+';
else
{
var charCode = clearString.charCodeAt(x);
var hexVal = charCode.toString(16);
output += '％' + ( hexVal.length < 2 ? '0' : '' ) + hexVal.toUpperCase();
}
x++;
}
}

function utf16to8(str)
{
var out, i, len, c;

out = "";
len = str.length;
for(i = 0; i < len; i++)
{
c = str.charCodeAt(i);
if ((c >= 0x0001) && (c <= 0x007F))
{
out += str.charAt(i);
}
else if (c > 0x07FF)
{
out += String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));
out += String.fromCharCode(0x80 | ((c >> 6) & 0x3F));
out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
}
else
{
out += String.fromCharCode(0xC0 | ((c >> 6) & 0x1F));
out += String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
}
}
return out;
}

return output;
}

2、urldecode

使用方法：urldecode(url);

function urldecode(encodedString)
{
var output = encodedString;
var binVal, thisString;
var myregexp = /(％[^％]{2})/;
function utf8to16(str)
{
var out, i, len, c;
var char2, char3;

out = "";
len = str.length;
i = 0;
while(i < len)
{
c = str.charCodeAt(i++);
switch(c >> 4)
{
case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
out += str.charAt(i-1);
break;
case 12: case 13:
char2 = str.charCodeAt(i++);
out += String.fromCharCode(((c & 0x1F) << 6) | (char2 & 0x3F));
break;
case 14:
char2 = str.charCodeAt(i++);
char3 = str.charCodeAt(i++);
out += String.fromCharCode(((c & 0x0F) << 12) |
((char2 & 0x3F) << 6) |
((char3 & 0x3F) << 0));
break;
}
}
return out;
}
while((match = myregexp.exec(output)) != null
&& match.length > 1
&& match[1] != '')
{
binVal = parseInt(match[1].substr(1),16);
thisString = String.fromCharCode(binVal);
output = output.replace(match[1], thisString);
}

//output = utf8to16(output);
output = output.replace(/\\+/g, " ");
output = utf8to16(output);
return output;
}

当服务器端通过php的urlencode转码的就可以使用js的urldecode进行解析即可。