PHP下载文件的代码总结

$file_dir="upload/";
$file_name=$_GET['name']; //服务器的真实文件名
$file   =   fopen($file_dir   .   $file_name, "r ");   //   打开文件  
 //   输入文件标签
 Header( "Content-type:  application/octet-stream  "); 
 Header( "Accept-Ranges:   bytes ");
 Header( "Accept-Length:   ".filesize($file_dir   .   $file_name));
 Header( "Content-Disposition:   attachment;   filename= "  .basename(  $file_name));
 //   输出文件内容
 echo   fread($file,filesize($file_dir   .   $file_name));
 fclose($file);
 exit;

做个补充：以下代码来源北邮人论坛它的功能是针对各种MIME类型文件在常用浏览器下直接能打开的下载。

$array=explode(".",$file_name);
$type=$array[count($array)-1];
switch($type) {  
        case 'jar': $mime = "application/java-archive"; break;  
        case 'zip': $mime = "application/zip"; break;  
        case 'jpeg': $mime = "image/jpeg"; break;  
        case 'jpg': $mime = "image/jpg"; break;  
        case 'jad': $mime = "text/vnd.sun.j2me.app-descriptor"; break;  
        case "gif": $mime = "image/gif"; break;  
        case "png": $mime = "image/png"; break;  
        case "pdf": $mime = "application/pdf"; break;  
        case "txt": $mime = "text/plain"; break;  
        case "doc": $mime = "application/msword"; break;  
        case "docx": $mime = "application/msword"; break;  
        case "ppt": $mime = "application/vnd.ms-powerpoint"; break;  
        case "wbmp": $mime = "image/vnd.wap.wbmp"; break;  
        case "wmlc": $mime = "application/vnd.wap.wmlc"; break;  
        case "mp4s": $mime = "application/mp4"; break;  
        case "ogg": $mime = "application/ogg"; break;  
        case "pls": $mime = "application/pls+xml"; break;  
        case "asf": $mime = "application/vnd.ms-asf"; break;  
        case "swf": $mime = "application/x-shockwave-flash"; break;  
        case "mp4": $mime = "video/mp4"; break;  
        case "m4a": $mime = "audio/mp4"; break;  
        case "m4p": $mime = "audio/mp4"; break;  
        case "mp4a": $mime = "audio/mp4"; break;  
        case "mp3": $mime = "audio/mpeg"; break;  
        case "m3a": $mime = "audio/mpeg"; break;  
        case "m2a": $mime = "audio/mpeg"; break;  
        case "mp2a": $mime = "audio/mpeg"; break;  
        case "mp2": $mime = "audio/mpeg"; break;  
        case "mpga": $mime = "audio/mpeg"; break;  
        case "wav": $mime = "audio/wav"; break;  
        case "m3u": $mime = "audio/x-mpegurl"; break;  
        case "bmp": $mime = "image/bmp"; break;  
        case "ico": $mime = "image/x-icon"; break;  
        case "3gp": $mime = "video/3gpp"; break;  
        case "3g2": $mime = "video/3gpp2"; break;  
        case "mp4v": $mime = "video/mp4"; break;  
        case "mpg4": $mime = "video/mp4"; break;  
        case "m2v": $mime = "video/mpeg"; break;  
        case "m1v": $mime = "video/mpeg"; break;  
        case "mpe": $mime = "video/mpeg"; break;  
        case "mpeg": $mime = "video/mpeg"; break;  
        case "mpg": $mime = "video/mpeg"; break;  
        case "mov": $mime = "video/quicktime"; break;  
        case "qt": $mime = "video/quicktime"; break;  
        case "avi": $mime = "video/x-msvideo"; break;  
        case "midi": $mime = "audio/midi"; break;  
        case "mid": $mime = "audio/mid"; break;  
        case "amr": $mime = "audio/amr"; break;  
        default: $mime = "application/force-download";  //强制下载
    }  
 用 Header('Content-Type: '.$mime); 可替代上面Header( "Content-type:  application/octet-stream  "); 代码。