PHP 實現explort() 功能

<?php/** * @author:xiaojiang * PHP 實現explort();功能 */$str = ',1,2,3,4,321321,aaa,bbb';function myExplode($seg,$str,$limit=0){   $_ret = array(0=>'');   $len = strlen($str);   $slen = strlen($seg);   $_limit = 0;   for($i=0; $i<$len; $i++){      if(substr($str,$i,$slen) == $seg ){          $_limit++;          $i += $slen-1;           continue;      }else{          $_ret[$_limit] .= $str[$i];       }   }   if($limit < 0 )      $_ret = array_slice($_ret, 0 , $limit );   else{      $_ret = $limit >= count($_ret) ? $_ret :  array_merge(array_slice($_ret, 0 , $limit-1 ), array(implode( $seg , array_slice($_ret,$limit-1))));   }   return $_ret;}var_dump(myExplode("4",$str));echo "<br>";var_dump(explode("4",$str));echo "<br>";?>

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