public function downFile($path = ''){    if(!$path) header("Location: /");    download($path);  }

function download($file_url,$new_name=''){     if(!isset($file_url)||trim($file_url)==''){       echo '500';     }     if(!file_exists($file_url)){ //檢查文件是否存在       echo '404';     }     $file_name=basename($file_url);     $file_type=explode('.',$file_url);     $file_type=$file_type[count($file_type)-1];     $file_name=trim($new_name=='')?$file_name:urlencode($new_name);     $file_type=fopen($file_url,'r'); //打開文件     //輸入文件標簽     header("Content-type: application/octet-stream");     header("Accept-Ranges: bytes");     header("Accept-Length: ".filesize($file_url));     header("Content-Disposition: attachment; filename=".$file_name);     //輸出文件內容     echo fread($file_type,filesize($file_url));     fclose($file_type);} 

<iframe id="iframe" src="" style="display: none;"></iframe>$(function(){      $('.downLoad').click(function(){        var path = $(this).attr('path');        $('#iframe').attr('src',"php文件路徑?path="+path);      })    })