<script language=vbs> OPTION EXPLICIT const BASE_64_MAP_INIT="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/" dim nl dim Base64EncMap(63) dim Base64DecMap(127) PUBLIC SUB initCodecs() nl = "<P>" & chr(13) & chr(10) dim max, idx max = len(BASE_64_MAP_INIT) for idx = 0 to max - 1 Base64EncMap(idx) = mid(BASE_64_MAP_INIT, idx + 1, 1) next for idx = 0 to max - 1 Base64DecMap(ASC(Base64EncMap(idx))) = idx next END SUB PUBLIC FUNCTION base64Encode(plain) if len(plain) = 0 then base64Encode = "" exit function end if dim ret, ndx, by3, first, second, third by3 = (len(plain) \ 3) * 3 ndx = 1 do while ndx <= by3 first = asc(mid(plain, ndx+0, 1)) second = asc(mid(plain, ndx+1, 1)) third = asc(mid(plain, ndx+2, 1)) ret = ret & Base64EncMap( (first \ 4) AND 63 ) ret = ret & Base64EncMap( ((first * 16) AND 48) + ((second \ 16)AND 15 ) ) ret = ret & Base64EncMap( ((second * 4) AND 60) + ((third \ 64)AND 3 ) ) ret = ret & Base64EncMap( third AND 63) ndx = ndx + 3 loop if by3 < len(plain) then first = asc(mid(plain, ndx+0, 1)) ret = ret & Base64EncMap( (first \ 4) AND 63 ) if (len(plain) MOD 3 ) = 2 then second = asc(mid(plain, ndx+1, 1)) ret = ret & Base64EncMap( ((first * 16) AND 48) +((second \16) AND 15 ) ) ret = ret & Base64EncMap( ((second * 4) AND 60) ) else ret = ret & Base64EncMap( (first * 16) AND 48) ret = ret & "=" end if ret = ret & "=" end if base64Encode = ret END FUNCTION PUBLIC FUNCTION base64Decode(scrambled) if len(scrambled) = 0 then base64Decode = "" exit function end if dim realLen realLen = len(scrambled) do while mid(scrambled, realLen, 1) = "=" realLen = realLen - 1 loop dim ret, ndx, by4, first, second, third, fourth ret = "" by4 = (realLen \ 4) * 4 ndx = 1 do while ndx <= by4 first = Base64DecMap(asc(mid(scrambled, ndx+0, 1))) second = Base64DecMap(asc(mid(scrambled, ndx+1, 1))) third = Base64DecMap(asc(mid(scrambled, ndx+2, 1))) fourth = Base64DecMap(asc(mid(scrambled, ndx+3, 1))) ret = ret & chr( ((first * 4) AND 255)+((second\16) AND 3)) ret = ret & chr( ((second * 16) AND 255) + ((third \ 4) AND 15) ) ret = ret & chr( ((third * 64) AND 255) + (fourth AND 63) ) ndx = ndx + 4 loop if ndx < realLen then first = Base64DecMap(asc(mid(scrambled, ndx+0, 1))) second = Base64DecMap(asc(mid(scrambled, ndx+1, 1))) ret = ret & chr( ((first * 4) AND 255) +((second \ 16) AND 3)) if realLen MOD 4 = 3 then third = Base64DecMap(asc(mid(scrambled,ndx+2,1))) ret = ret & chr( ((second * 16) AND 255) + ((third \ 4) AND 15) ) end if end if base64Decode = ret END FUNCTION' 首先初始化 call initCodecs </script> <input id=a1><br> <input type=button value=编码 onclick="encoded.value= base64Encode(a1.value)"> <input id=encoded><br> <input type=button value=解码 onclick="decoded.value= base64Decode(encoded.value)"> <input id=decoded>
OPTION EXPLICIT
const BASE_64_MAP_INIT="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
dim nl dim Base64EncMap(63)
dim Base64DecMap(127) PUBLIC SUB initCodecs()
nl = "<P>" & chr(13) & chr(10)
dim max, idx
max = len(BASE_64_MAP_INIT)
for idx = 0 to max - 1
Base64EncMap(idx) = mid(BASE_64_MAP_INIT, idx + 1, 1)
next
for idx = 0 to max - 1
Base64DecMap(ASC(Base64EncMap(idx))) = idx
next
END SUB PUBLIC FUNCTION base64Encode(plain) if len(plain) = 0 then
base64Encode = ""
exit function
end if dim ret, ndx, by3, first, second, third
by3 = (len(plain) \ 3) * 3
ndx = 1
do while ndx <= by3
first = asc(mid(plain, ndx+0, 1))
second = asc(mid(plain, ndx+1, 1))
third = asc(mid(plain, ndx+2, 1))
ret = ret & Base64EncMap( (first \ 4) AND 63 )
ret = ret & Base64EncMap( ((first * 16) AND 48) + ((second \ 16)AND 15 ) )
ret = ret & Base64EncMap( ((second * 4) AND 60) + ((third \ 64)AND 3 ) )
ret = ret & Base64EncMap( third AND 63)
ndx = ndx + 3
loop if by3 < len(plain) then
first = asc(mid(plain, ndx+0, 1))
ret = ret & Base64EncMap( (first \ 4) AND 63 )
if (len(plain) MOD 3 ) = 2 then
second = asc(mid(plain, ndx+1, 1))
ret = ret & Base64EncMap( ((first * 16) AND 48) +((second \16) AND 15 ) )
ret = ret & Base64EncMap( ((second * 4) AND 60) )
else
ret = ret & Base64EncMap( (first * 16) AND 48)
ret = ret & "="
end if
ret = ret & "="
end if base64Encode = ret
END FUNCTION PUBLIC FUNCTION base64Decode(scrambled) if len(scrambled) = 0 then
base64Decode = ""
exit function
end if dim realLen
realLen = len(scrambled)
do while mid(scrambled, realLen, 1) = "="
realLen = realLen - 1
loop
dim ret, ndx, by4, first, second, third, fourth
ret = ""
by4 = (realLen \ 4) * 4
ndx = 1
do while ndx <= by4
first = Base64DecMap(asc(mid(scrambled, ndx+0, 1)))
second = Base64DecMap(asc(mid(scrambled, ndx+1, 1)))
third = Base64DecMap(asc(mid(scrambled, ndx+2, 1)))
fourth = Base64DecMap(asc(mid(scrambled, ndx+3, 1)))
ret = ret & chr( ((first * 4) AND 255)+((second\16) AND 3))
ret = ret & chr( ((second * 16) AND 255) + ((third \ 4) AND 15) )
ret = ret & chr( ((third * 64) AND 255) + (fourth AND 63) )
ndx = ndx + 4
loop if ndx < realLen then
first = Base64DecMap(asc(mid(scrambled, ndx+0, 1)))
second = Base64DecMap(asc(mid(scrambled, ndx+1, 1)))
ret = ret & chr( ((first * 4) AND 255) +((second \ 16) AND 3))
if realLen MOD 4 = 3 then
third = Base64DecMap(asc(mid(scrambled,ndx+2,1)))
ret = ret & chr( ((second * 16) AND 255) + ((third \ 4) AND 15) )
end if
end if base64Decode = ret
END FUNCTION' 首先初始化
call initCodecs
</script>
<input id=a1><br>
<input type=button value=编码 onclick="encoded.value= base64Encode(a1.value)">
<input id=encoded><br>
<input type=button value=解码 onclick="decoded.value= base64Decode(encoded.value)">
<input id=decoded>
* Version: 1.0
* LastModified: Dec 25 1999
* This library is free. You can redistribute it and/or modify it.
*//* 本程序仅限于对ASCII字符进行base64编码/解码,不支持中文
* Interfaces:
* b64 = base64encode(data);
* data = base64decode(b64);
*/
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;
}