短URL实现

<?php

/**

* Created by PhpStorm.

* User: yangyulong/[email protected]

* Date: 2015/5/28

* Time: 15:55

*/

functionshortUrl($url){

$base32=array(

‘a‘,‘b‘,‘c‘,‘d‘,‘e‘,‘f‘,‘g‘,‘h‘,

‘i‘,‘j‘,‘k‘,‘l‘,‘m‘,‘n‘,‘o‘,‘p‘,

‘q‘,‘r‘,‘s‘,‘t‘,‘u‘,‘v‘,‘w‘,‘x‘,

‘y‘,‘z‘,‘0‘,‘1‘,‘2‘,‘3‘,‘4‘,‘5‘

);

$hex= md5($url);

$hexLength=strlen($hex);

$subHexLen=$hexLength/ 8;

$output=array();

for($i= 0;$i<$subHexLen;$i++) {

//每循环一次取到8位

$subHex=substr($hex,$i* 8, 8);

$int= 0x3FFFFFFF & (1 * (‘0x‘.$subHex));

$out=‘‘;

for($j= 0;$j< 6;$j++) {

$val= 0x0000001F &$int;

$out.=$base32[$val];

$int=$int>> 5;

}

$output[] =$out;

}

return$output;

}

functionshortUrl2($url){

$result= sprintf("%u",crc32($url));

$show=‘‘;

while($result >0){

$s=$result% 62;

if($s> 35){

$s=chr($s+61);

}elseif($s>9 &&$s<=35){

$s=chr($s+55);

}

$show.=$s;

$result=floor($result/ 62);

}

return$show;

}

echoshortUrl2(‘http://baidu.com‘);