php图像下载链接不起作用


Php Image Download Link not Working

我已经尝试使用以下代码下载图像,但它在我的计算机中的本地主机中工作,但是当站点在托管服务上实时,当我单击下载链接时,显示一条消息
已发送的标头

不下载图像。请给我解决。

链接使用:

print'<p><a href="?u=download&file=nplace_image/'. $rs[$i][16].'" class="btn"><i class="icon-cloud-download"></i> Download</a></p>';

我的代码:

<?php
$file = $_GET['file'];
download_file($file);
function download_file( $fullPath ){
  // Must be fresh start
  if( headers_sent() )
    die('Headers Sent');
  // Required for some browsers
  if(ini_get('zlib.output_compression'))
    ini_set('zlib.output_compression', 'Off');
  // File Exists?
  if( file_exists($fullPath) ){
    // Parse Info / Get Extension
    $fsize = filesize($fullPath);
    $path_parts = pathinfo($fullPath);
    $ext = strtolower($path_parts["extension"]);
    // Determine Content Type
    switch ($ext) {
      case "pdf": $ctype="application/pdf"; break;
      case "exe": $ctype="application/octet-stream"; break;
      case "zip": $ctype="application/zip"; break;
      case "doc": $ctype="application/msword"; break;
      case "xls": $ctype="application/vnd.ms-excel"; break;
      case "ppt": $ctype="application/vnd.ms-powerpoint"; break;
      case "gif": $ctype="image/gif"; break;
      case "png": $ctype="image/png"; break;
      case "jpeg":
      case "jpg": $ctype="image/jpg"; break;
      default: $ctype="application/force-download";
    }
    header("Pragma: public"); // required
    header("Expires: 0");
    header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
    header("Cache-Control: private",false); // required for certain browsers
    header("Content-Type: $ctype");
    header("Content-Disposition: attachment; filename='"".basename($fullPath)."'";" );
    header("Content-Transfer-Encoding: binary");
    header("Content-Length: ".$fsize);
    ob_clean();
    flush();
    readfile( $fullPath );
  } else
    die('File Not Found');
}
?>
看起来在

执行下载代码之前输出了一些东西。所以它显示了这个消息。您可以检查服务器是否在错误日志文件中记录任何内容。您也可以在调用 download_file 函数之前尝试ob_clean。

使用以下代码:

    <?php
    if(isset($_GET['file'])) {
    $file = isset($_GET['file'])?$_GET['file']:'';
    download_file($file);
    }
    function download_file( $fullPath ){
      // Must be fresh start
      if( headers_sent() )
        die('Headers Sent');
      // Required for some browsers
      if(ini_get('zlib.output_compression'))
        ini_set('zlib.output_compression', 'Off');
      // File Exists?
      if( file_exists($fullPath) ){
        // Parse Info / Get Extension
        $fsize = filesize($fullPath);
        $path_parts = pathinfo($fullPath);
        $ext = strtolower($path_parts["extension"]);
        // Determine Content Type
        switch ($ext) {
          case "pdf": $ctype="application/pdf"; break;
          case "exe": $ctype="application/octet-stream"; break;
          case "zip": $ctype="application/zip"; break;
          case "doc": $ctype="application/msword"; break;
          case "xls": $ctype="application/vnd.ms-excel"; break;
          case "ppt": $ctype="application/vnd.ms-powerpoint"; break;
          case "gif": $ctype="image/gif"; break;
          case "png": $ctype="image/png"; break;
          case "jpeg":
          case "jpg": $ctype="image/jpg"; break;
          default: $ctype="application/force-download";
        }
        header("Pragma: public"); // required
        header("Expires: 0");
        header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
        header("Cache-Control: private",false); // required for certain browsers
        header("Content-Type: $ctype");
        header("Content-Disposition: attachment; filename='"".basename($fullPath)."'";" );
        header("Content-Transfer-Encoding: binary");
        header("Content-Length: ".$fsize);
        ob_clean();
        flush();
        readfile( $fullPath );
} else
    die('File Not Found');
}
?>
    <?php print'<p><a href="?u=download&file=noteII007.jpg" class="btn"><i class="icon-cloud-   download"></i> Download</a></p>';?>