JS implementation Base64 encryption and decryption

Last Update:2016-05-24 Source: Internet

Author: User

Tags 0xc0 base64 encode

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JS implementation Base64 encryption and decryption
Reprinted from Http://blog.csdn.net/fengzheng0306/archive/2006/04/25/676055.aspx

Method One:

<HTML>
<HEAD>
<TITLE>Base64</TITLE>
<script language=javascript>
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, 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 >> b) & 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))
}
</script>
</HEAD>
<BODY>
<H1>Base64</H1>
<form name= "F" >
Original Code <BR>
<textarea name= "source" rows=4 cols=60 wrap= "soft" ></TEXTAREA><BR><BR>
Base64 encode<br>
<textarea name= "Output" rows=4 cols=60 wrap= "soft" ></TEXTAREA><BR><BR>
Base64 decode<br>
<textarea name= "decode" rows=4 cols=60 wrap= "soft" ></TEXTAREA><BR><BR>
<input Type=button value= "Convert" onclick= "doit ()" >
</FORM>
</BODY>

Method Two:

/**** Base64 encode/decode** @author haitao.tu* @date 2010-04-26* @email [email protected]**/function Base6 4 () {//Private PROPERTY_KEYSTR = "abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz0123456789+/=";//Public Method for encodingthis.encode = function (input) {var output = ""; var chr1, CHR2, CHR3, Enc1, Enc2, enc3, Enc4;var i = 0;  input = _utf8_encode (input), while (I < input.length) {chr1 = Input.charcodeat (i++); chr2 = Input.charcodeat (i++); chr3 = Input.charcodeat (i++); enc1 = chr1 >> 2;enc2 = ((Chr1 & 3) << 4) | (CHR2 >> 4); enc3 = ((CHR2 &) << 2) | (CHR3 >> 6); Enc4 = Chr3 & 63;if (IsNaN (CHR2)) {enc3 = Enc4 =;} else if (IsNaN (CHR3)) {Enc4 = 64;} Output = output +_keystr.charat (enc1) + _keystr.charat (ENC2) +_keystr.charat (enc3) + _keystr.charat (ENC4);} return output;} Public method for Decodingthis.decode = function (input) {var output = ""; var chr1, CHR2, Chr3;var enc1, Enc2, enc3, en C4;var i = 0;input = input.Replace (/[^a-za-z0-9\+\/\=]/g, ""), while (I < input.length) {enc1 = _keystr.indexof (Input.charat (i++)); Enc2 = _ Keystr.indexof (Input.charat (i++)); enc3 = _keystr.indexof (Input.charat (i++)); Enc4 = _keystr.indexof (Input.charat (i+ +)); chr1 = (enc1 << 2) | (Enc2 >> 4); chr2 = ((Enc2 &) << 4) | (enc3 >> 2); chr3 = ((enc3 & 3) << 6) | Enc4;output = output + String.fromCharCode (CHR1), if (enc3! =) {output = output + String.fromCharCode (CHR2);} if (enc4! =) {output = output + String.fromCharCode (CHR3);}} Output = _utf8_decode (output); return output;} Private method for UTF-8 Encoding_utf8_encode = function (string) {string = String.Replace (/\r\n/g, "\ n"); var utftext = ""; for (var n = 0; n < string.length;  n++) {var c = string.charcodeat (n), if (C < +) {Utftext + = String.fromCharCode (c);} else if ((C > 127) && (c < 2048)) {Utftext + = String.fromCharCode ((c >> 6) | 192); Utftext + = String.fromCharCode ((c & N) |);} EL Se{Utftext + = String.fromCharCode ((c >> b) | 224) Utftext + = String.fromCharCode ((((c >> 6) & ()); UTF Text + = String.fromCharCode ((C & 63) | 128);} }return Utftext;}  Private method for UTF-8 Decoding_utf8_decode = function (utftext) {var string = ""; var i = 0;var c = C1 = C2 = 0;while (I < Utftext.length)  {c = utftext.charcodeat (i), if (C < +) {string + = String.fromCharCode (c); i++;} else if ((C > 191) && (C < 224) {C2 = Utftext.charcodeat (i+1); string + = String.fromCharCode (((C & D) << 6) | (C2 & 63)); i + = 2;}  else {c2 = Utftext.charcodeat (i+1); C3 = Utftext.charcodeat (i+2); string + = String.fromCharCode (((C & D) << 12) | ((C2 &) << 6) | (C3 & 63)); i + = 3;}} return string;}}

<!DOCTYPE HTML>
<Html>
<Head>
<MetaCharSet= "Utf-8">
<Title&GT;BASE64 Encryption and decryption</Title>
<ScriptType= "Text/javascript"> 
 VarB=NewBase64 ();
 VarStr=B.encode ("Admin:admin");
Alert"Base64 encode:"+STR);
Decrypt
Str=B.decode (str);
Alert"Base64 Decode:"+STR);
</Script>
</Head>

<Body>
</Body>
</Html>

Method Three:
/**
 * 
* Btoa (): string or binary value converted to BASE64 encoding
* Atob (): BASE64 encoding to original encoding
  */
var string = ' Hello world! ';
Console.log (Btoa (String))//"SGVSBG8GV29YBGQH"
Console.log (Atob (' SGVSBG8GV29YBGQH '))//"Hello world!"

function B64encode (str) {
return Btoa (encodeURIComponent (str));
  }

function B64decode (str) {
return decodeURIComponent (Atob (str));
  }
Console.log (B64encode (' Hello world! Hello! '))
Console.log (B64decode (' sgvsbg8lmjbxb3jszcelmjalrtqlqkqlqtalrtulqtulqkqlruylqkmlode= '))

JS implementation Base64 encryption and decryption

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