encode64可以获得最短的由26个英文大小写字母数字加上"-_"两个符号编码的数据,这个个字串可以在网络自由传输,无需考虑被自动转码引起的混乱. 缺点: 对于大字串太慢了,原因不明,可能PHP脚本本身就是慢,所以它内置 很多函数,这些函数如果用脚本来实现是不可忍受的. 而JavaScript就没这个问题,脚本的速度快的多.
/**
* PHP encode64编码类代码
*
* @param
* @arrange 512-笔记网： 512Pic.com
**/
<?PHP
//encode64编码可以同时取代encodeURI,encodeURIComponent,endode函数,因为选取的这些字符都不会被编码.
class Encode64{
function code($str) {
$KEY = 'PaAwO65goUf7IK2vi9-xq8cFTEXLCDY1Hd3tV0ryzjbpN_BlnSs4mGRkQWMZJeuh';
$a = StrToBytes($str);
$len = count($a);
$res = $len % 3;
$s = "";$i = 2;$v = 0;
for (; $i < $len; $i += 3) {
$v = $a[$i - 2] + ($a[$i - 1] << 8) + ($a[$i] << 16);
$s .= $KEY[$v & 0x3f];
$s .= $KEY[($v >> 6) & 0x3f];
$s .= $KEY[($v >> 12) & 0x3f];
$s .= $KEY[($v >> 18)];
}
if ($res == 1) {
$v = $a[$i - 2];
$s .= $KEY[$v & 0x3f];
$s .= $KEY[($v >> 6) & 0x3f];
} else if ($res == 2) {
$v = $a[$i - 2] + ($a[$i - 1] << 8);
$s .= $KEY[$v & 0x3f];
$s .= $KEY[($v >> 6) & 0x3f];
$s .= $KEY[($v >> 12) & 0x3f];
}
return $s;
}
function decode($codeStr) {
$KEY = 'PaAwO65goUf7IK2vi9-xq8cFTEXLCDY1Hd3tV0ryzjbpN_BlnSs4mGRkQWMZJeuh';
$dic = array();
for ($i = 0; $i < 64; $i++) {
$dic[$KEY[$i]] = $i;
}
$len = strlen($codeStr);
$res = $len % 4;
$cLen = floor($len/4)*3;
if($res==2) $clen += 1;
elseif($res==3) $clen += 2;
$code = range(0,$clen);
$i = 3;$v = 0; $j = 0;
for (; $i < $len; $i += 4) {
$v = $dic[$codeStr[$i - 3]];
$v += $dic[$codeStr[$i - 2]] << 6;
$v += $dic[$codeStr[$i - 1]] << 12;
$v += $dic[$codeStr[$i]] << 18;
$code[$j] = $v & 0xff;
$code[$j+1] = ($v >> 8) & 0xff;
$code[$j+2] = ($v >> 16) & 0xff;
$j += 3;
}
if ($res == 2) {//正确的字节数肯定是余2或3,没有1的情况,如果出现,舍弃.
$v = $dic[$codeStr[$i - 3]];
$v += $dic[$codeStr[$i - 2]] << 6;
$code[$j] = $v & 0xff;
} else if ($res == 3) {
$v = $dic[$codeStr[$i - 3]];
$v += $dic[$codeStr[$i - 2]] << 6;
$v += $dic[$codeStr[$i - 1]] << 12;
$code[$j] = $v & 0xff;
$code[$j+1] = ($v >> 8) & 0xff;
}
return BytesToStr($code);
}
}
function BytesToStr($bytes) {
$str = '';
foreach($bytes as $ch) {
$str .= chr($ch);
}
return iconv('UTF-16BE','utf-8',$str);
}
function StrToBytes($str) {
$str = iconv('utf-8','UTF-16BE',$str);
$len = strlen($str);
$bytes = array();
for($i=0;$i<$len;$i++) {
$bytes[] = ord($str[$i]) ;
}
return $bytes;//来自 5 1 2 p i c .c o m
}
