常用JS加密编码算法代码第1/2页

function URLEncode(Str){ 
if(Str==null||Str=="") 
return ""; 
var newStr=""; 
function toCase(sStr){ 
return sStr.toString(16).toUpperCase(); 
} 
for(var i=0,icode,len=Str.length;i<len;i++){ 
icode=Str.charCodeAt(i); 
if( icode<0x10) 
newStr+="%0"+icode.toString(16).toUpperCase(); 
else if(icode<0x80){ 
if(icode==0x20) 
newStr+="+"; 
else if((icode>=0x30&&icode<=0x39)||(icode>=0x41&&icode<=0x5A)||(icode>=0x61&&icode<=0x7A)) 
newStr+=Str.charAt(i); 
else 
newStr+="%"+toCase(icode); 
} 
else if(icode<0x800){ 
newStr+="%"+toCase(0xC0+(icode>>6)); 
newStr+="%"+toCase(0x80+icode%0x40); 
} 
else{ 
newStr+="%"+toCase(0xE0+(icode>>12)); 
newStr+="%"+toCase(0x80+(icode>>6)%0x40); 
newStr+="%"+toCase(0x80+icode%0x40); 
} 
} 
return newStr; 
}

var base64EncodeChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"; 
var base64DecodeChars = new Array( 
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 62, -1, -1, -1, 63, 
52, 53, 54, 55, 56, 57, 58, 59, 60, 61, -1, -1, -1, -1, -1, -1, 
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, -1, -1, -1, -1, -1, 
-1, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 
41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, -1, -1, -1, -1, -1); 
function base64encode(str) { 
var out, i, len; 
var c1, c2, c3; 
len = str.length; 
i = 0; 
out = ""; 
while(i < len) { 
c1 = str.charCodeAt(i++) & 0xff; 
if(i == len) 
{ 
out += base64EncodeChars.charAt(c1 >> 2); 
out += base64EncodeChars.charAt((c1 & 0x3) << 4); 
out += "=="; 
break; 
} 
c2 = str.charCodeAt(i++); 
if(i == len) 
{ 
out += base64EncodeChars.charAt(c1 >> 2); 
out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4)); 
out += base64EncodeChars.charAt((c2 & 0xF) << 2); 
out += "="; 
break; 
} 
c3 = str.charCodeAt(i++); 
out += base64EncodeChars.charAt(c1 >> 2); 
out += base64EncodeChars.charAt(((c1 & 0x3)<< 4) | ((c2 & 0xF0) >> 4)); 
out += base64EncodeChars.charAt(((c2 & 0xF) << 2) | ((c3 & 0xC0) >>6)); 
out += base64EncodeChars.charAt(c3 & 0x3F); 
} 
return out; 
} 
function base64decode(str) { 
var c1, c2, c3, c4; 
var i, len, out; 
len = str.length; 
i = 0; 
out = ""; 
while(i < len) { 
/* c1 */ 
do { 
c1 = base64DecodeChars[str.charCodeAt(i++) & 0xff]; 
} while(i < len && c1 == -1); 
if(c1 == -1) 
break; 
/* c2 */ 
do { 
c2 = base64DecodeChars[str.charCodeAt(i++) & 0xff]; 
} while(i < len && c2 == -1); 
if(c2 == -1) 
break; 
out += String.fromCharCode((c1 << 2) | ((c2 & 0x30) >> 4)); 
/* c3 */ 
do { 
c3 = str.charCodeAt(i++) & 0xff; 
if(c3 == 61) 
return out; 
c3 = base64DecodeChars[c3]; 
} while(i < len && c3 == -1); 
if(c3 == -1) 
break; 
out += String.fromCharCode(((c2 & 0XF) << 4) | ((c3 & 0x3C) >> 2)); 
/* c4 */ 
do { 
c4 = str.charCodeAt(i++) & 0xff; 
if(c4 == 61) 
return out; 
c4 = base64DecodeChars[c4]; 
} while(i < len && c4 == -1); 
if(c4 == -1) 
break; 
out += String.fromCharCode(((c3 & 0x03) << 6) | c4); 
} 
return out; 
} 
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; 
} 
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: 
// 0xxxxxxx 
out += str.charAt(i-1); 
break; 
case 12: case 13: 
// 110x xxxx 10xx xxxx 
char2 = str.charCodeAt(i++); 
out += String.fromCharCode(((c & 0x1F) << 6) | (char2 & 0x3F)); 
break; 
case 14: 
// 1110 xxxx 10xx xxxx 10xx xxxx 
char2 = str.charCodeAt(i++); 
char3 = str.charCodeAt(i++); 
out += String.fromCharCode(((c & 0x0F) << 12) | 
((char2 & 0x3F) << 6) | 
((char3 & 0x3F) << 0)); 
break; 
} 
} 
return out; 
} 
function doit() { 
var f = document.f 
f.output.value = base64encode(utf16to8(f.source.value)) 
f.decode.value = utf8to16(base64decode(f.output.value)) 
}