JavaScript URL encoding and decoding functions

JavaScript tutorial URL encoding and decoding function
function UrlEncode (str)
{
var ret= "";
var strspecial= "!" #$%& () *+,/:;<=>? []^`{|} ~%"; var tt= "";
for (Var i=0;i<str.length;i++)
{
var chr = Str.charat (i);
var c=str2asc (CHR);
tt + + chr+ ":" +c+ "n";
if (parseint ("0x" +c) > 0x7f)
{
ret+= "%" +c.slice (0,2) + "%" +c.slice (-2);
}
Else
{
if (chr== "")
ret+= "+";
else if (Strspecial.indexof (CHR)!=-1)
ret+= "%" +c.tostring (16);
Else
RET+=CHR;
}
}
return ret;
}

function UrlDecode (str) {
var ret= "";
for (Var i=0;i<str.length;i++)
{
var chr = Str.charat (i);
if (Chr = = "+")
{
ret+= "";
}
else if (chr== "%")
{
var asc = str.substring (i+1,i+3);
if (parseint ("0x" +asc) >0x7f)
{
Ret+=asc2str (parseint ("0x" +asc+str.substring (i+4,i+6));
i+=5;
}
Else
{
Ret+=asc2str (parseint ("0x" +asc));
i+=2;
}
}
Else
{
ret+= CHR;
}
}
return ret;
}