php代码片段

protected function _getExtension($fileInfo){
	    $fileName='';
		if($fileInfo){
		    foreach($fileInfo as $value){
			    $fileName=$value['name'];
			}
			$exts=preg_split("[/.]",$fileName);
			$n=count($exts)-1;
			$exts=$exts[$n];
			return $exts;
		}
	}

protected function _makePassword($length){
	   $possible="0123456789!@#$%^&*()_+abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
	   $str="";
	   while(strlen($str)<$length){
	      $str.=substr($possible,(rand() % strlen($possible)),1);
	   }
	   return ($str);
	}