asp.net 下载有些资源如avi在ie中直接打开

最新推荐文章于 2022-07-11 14:34:38 发布

原创最新推荐文章于 2022-07-11 14:34:38 发布 · 2.3k 阅读

1 ·

CC 4.0 BY-SA版权

文章标签：

#asp.net #avi #ie #string #button #浏览器

.net 专栏收录该内容

83 篇文章

订阅专栏

本文介绍ASP.NET中通过不同方法实现文件下载的过程，包括使用TransmitFile、WriteFile、分块下载及流方式下载的具体实现。此外，还探讨了如何设置正确的MIME类型以确保文件能正确地触发浏览器的下载行为而非直接打开。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

asp.net response.ContentType 下载文件的四种方法

asp.net下载文件的常用方法 //TransmitFile实现下载 //TransmitFile实现下载 protected void Button1_Click1(object sender, EventArgs e) { string strFileName = "三部闲置设备管理系统操作手册IEMS.ppt"; Response.ContentType = "application/x-zip-compressed"; //Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312"); string filename = BLL.Config.PART_EM_UPLOAD_DOC + strFileName; //BLL.Config.PART_EM_UPLOAD_DOC 为路径 ("D:/EMUploadDoc/") Response.AddHeader("Content-Disposition", "attachment;filename=" +Server.UrlPathEncode(strFileName)); //Server.UrlPathEncode()解决文件名的乱码问题. Response.TransmitFile(filename); } //WriteFile实现下载 protected void Button2_Click(object sender, EventArgs e) { string fileName = "asd.txt";//客户端保存的文件名 string filePath = Server.MapPath("DownLoad/aaa.txt");//路径 FileInfo fileInfo = new FileInfo(filePath); Response.Clear(); Response.ClearContent(); Response.ClearHeaders(); Response.AddHeader("Content-Disposition", "attachment;filename=" + fileName); Response.AddHeader("Content-Length", fileInfo.Length.ToString()); Response.AddHeader("Content-Transfer-Encoding", "binary"); Response.ContentType = "application/octet-stream"; Response.ContentEncoding = System.Text.Encoding.GetEncoding("gb2312"); Response.WriteFile(fileInfo.FullName); Response.Flush(); Response.End(); } //WriteFile分块下载 protected void Button3_Click(object sender, EventArgs e) { string fileName = "aaa.txt";//客户端保存的文件名 string filePath = Server.MapPath("DownLoad/aaa.txt");//路径 System.IO.FileInfo fileInfo = new System.IO.FileInfo(filePath); if (fileInfo.Exists == true) { const long ChunkSize = 102400;//100K 每次读取文件，只读取100Ｋ，这样可以缓解服务器的压力 byte[] buffer = new byte[ChunkSize]; Response.Clear(); System.IO.FileStream iStream = System.IO.File.OpenRead(filePath); long dataLengthToRead = iStream.Length;//获取下载的文件总大小 Response.ContentType = "application/octet-stream"; Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName)); while (dataLengthToRead > 0 && Response.IsClientConnected) { int lengthRead = iStream.Read(buffer, 0, Convert.ToInt32(ChunkSize));//读取的大小 Response.OutputStream.Write(buffer, 0, lengthRead); Response.Flush(); dataLengthToRead = dataLengthToRead - lengthRead; } Response.Close(); } } //流方式下载 protected void Button4_Click(object sender, EventArgs e) { string fileName = "aaa.txt";//客户端保存的文件名 string filePath = Server.MapPath("DownLoad/aaa.txt");//路径 //以字符流的形式下载文件 FileStream fs = new FileStream(filePath, FileMode.Open); byte[] bytes = new byte[(int)fs.Length]; fs.Read(bytes, 0, bytes.Length); fs.Close(); Response.ContentType = "application/octet-stream"; //通知浏览器下载文件而不是打开 Response.AddHeader("Content-Disposition", "attachment; filename=" + HttpUtility.UrlEncode(fileName, System.Text.Encoding.UTF8)); Response.BinaryWrite(bytes); Response.Flush(); Response.End(); }

1.目的：实现avi，MP3等文件点击链接的时候，能够在打开的时候弹出是否保存或者直接打开的框，避免直接在ie中乱码打开。

2.本人实现的方式是使用Response.TransmitFile(tempdir); 的方法，此方法需要指定 Response.ContentType，否则ie会直接打开部分类型的文件，如果您单击这些链接，就会发现浏览器对每个文件类型的处理方式都不同，具体取决于注册了哪些助手应用程序来打开每个文件类型。默认情况下，如果您单击 .asp 页面、.html 页面、.jpg、.gif 或 .txt，它会在浏览器其本身中打开，并且不出现“另存为”对话框。这是因为这些文件的扩展名都属于已知的 MIME 类型。因此，要么浏览器本身知道如何呈现文件，要么操作系统具有一个将被浏览器使用的助手应用程序。Webcasts（.wmv、.avi 等等）、PodCasts（.mp3 或 .wma）、PowerPoint® 文件以及所有的 Microsoft® Office 文档都属于已知的 MIME 类型，如果您不想在默认情况下联机打开这些文件，就产生了一个难题。

刚开始的时候获取Response.ContentType的代码，比较不灵巧：

private static string MimeType(string strFileName) { string retval = ""; switch(Systm.IO.Path.GetExtension(strFileName).ToLower()) { case ".3dm": retval = "x-world/x-3dmf"; break; case ".3dmf": retval = "x-world/x-3dmf"; break; case ".a": retval = "application/octet-stream"; break; case ".aab": retval = "application/x-authorware-bin"; break; case ".aam": retval = "application/x-authorware-map"; break; case ".aas": retval = "application/x-authorware-seg"; break; case ".abc": retval = "text/vnd.abc"; break; case ".acgi": retval = "text/html"; break; case ".afl": retval = "video/animaflex"; break; case ".ai": retval = "application/postscript"; break; case ".aif": retval = "audio/aiff"; break; case ".aifc": retval = "audio/aiff"; break; case ".aiff": retval = "audio/aiff"; break; case ".aim": retval = "application/x-aim"; break; case ".aip": retval = "text/x-audiosoft-intra"; break; case ".ani": retval = "application/x-navi-animation"; break; case ".aos": retval = "application/x-nokia-9000-communicator-add-on-software"; break; case ".aps": retval = "application/mime"; break; case ".arc": retval = "application/octet-stream"; break; case ".arj": retval = "application/arj"; break; case ".art": retval = "image/x-jg"; break; case ".asf": retval = "video/x-ms-asf"; break; case ".asm": retval = "text/x-asm"; break; case ".asp": retval = "text/asp"; break; case ".asx": retval = "video/x-ms-asf"; break; case ".au": retval = "audio/basic"; break; case ".avi": retval = "video/avi"; break; case ".avs": retval = "video/avs-video"; break; case ".bcpio": retval = "application/x-bcpio"; break; case ".bin": retval = "application/octet-stream"; break; case ".bm": retval = "image/bmp"; break; case ".bmp": retval = "image/bmp"; break; case ".boo": retval = "application/book"; break; case ".book": retval = "application/book"; break; case ".boz": retval = "application/x-bzip2"; break; case ".bsh": retval = "application/x-bsh"; break; case ".bz": retval = "application/x-bzip"; break; case ".bz2": retval = "application/x-bzip2"; break; case ".c": retval = "text/plain"; break; case ".c++": retval = "text/plain"; break; case ".cat": retval = "application/vnd.ms-pki.seccat"; break; case ".cc": retval = "text/plain"; break; case ".ccad": retval = "application/clariscad"; break; case ".cco": retval = "application/x-cocoa"; break; case ".cdf": retval = "application/cdf"; break; case ".cer": retval = "application/pkix-cert"; break; case ".cha": retval = "application/x-chat"; break; case ".chat": retval = "application/x-chat"; break; case ".class": retval = "application/java"; break; case ".com": retval = "application/octet-stream"; break; case ".conf": retval = "text/plain"; break; case ".cpio": retval = "application/x-cpio"; break; case ".cpp": retval = "text/x-c"; break; case ".cpt": retval = "application/x-cpt"; break; case ".crl": retval = "application/pkcs-crl"; break; case ".crt": retval = "application/pkix-cert"; break; case ".csh": retval = "application/x-csh"; break; case ".css": retval = "text/css"; break; case ".cxx": retval = "text/plain"; break; case ".dcr": retval = "application/x-director"; break; case ".deepv": retval = "application/x-deepv"; break; case ".def": retval = "text/plain"; break; case ".der": retval = "application/x-x509-ca-cert"; break; case ".dif": retval = "video/x-dv"; break; case ".dir": retval = "application/x-director"; break; case ".dl": retval = "video/dl"; break; case ".doc": retval = "application/msword"; break; case ".dot": retval = "application/msword"; break; case ".dp": retval = "application/commonground"; break; case ".drw": retval = "application/drafting"; break; case ".dump": retval = "application/octet-stream"; break; case ".dv": retval = "video/x-dv"; break; case ".dvi": retval = "application/x-dvi"; break; case ".dwf": retval = "model/vnd.dwf"; break; case ".dwg": retval = "image/vnd.dwg"; break; case ".dxf": retval = "image/vnd.dwg"; break; case ".dxr": retval = "application/x-director"; break; case ".el": retval = "text/x-script.elisp"; break; case ".elc": retval = "application/x-elc"; break; case ".env": retval = "application/x-envoy"; break; case ".eps": retval = "application/postscript"; break; case ".es": retval = "application/x-esrehber"; break; case ".etx": retval = "text/x-setext"; break; case ".evy": retval = "application/envoy"; break; case ".exe": retval = "application/octet-stream"; break; case ".f": retval = "text/plain"; break; case ".f77": retval = "text/x-fortran"; break; case ".f90": retval = "text/plain"; break; case ".fdf": retval = "application/vnd.fdf"; break; case ".fif": retval = "image/fif"; break; case ".fli": retval = "video/fli"; break; case ".flo": retval = "image/florian"; break; case ".flx": retval = "text/vnd.fmi.flexstor"; break; case ".fmf": retval = "video/x-atomic3d-feature"; break; case ".for": retval = "text/x-fortran"; break; case ".fpx": retval = "image/vnd.fpx"; break; case ".frl": retval = "application/freeloader"; break; case ".funk": retval = "audio/make"; break; case ".g": retval = "text/plain"; break; case ".g3": retval = "image/g3fax"; break; case ".gif": retval = "image/gif"; break; case ".gl": retval = "video/gl"; break; case ".gsd": retval = "audio/x-gsm"; break; case ".gsm": retval = "audio/x-gsm"; break; case ".gsp": retval = "application/x-gsp"; break; case ".gss": retval = "application/x-gss"; break; case ".gtar": retval = "application/x-gtar"; break; case ".gz": retval = "application/x-gzip"; break; case ".gzip": retval = "application/x-gzip"; break; case ".h": retval = "text/plain"; break; case ".hdf": retval = "application/x-hdf"; break; case ".help": retval = "application/x-helpfile"; break; case ".hgl": retval = "application/vnd.hp-hpgl"; break; case ".hh": retval = "text/plain"; break; case ".hlb": retval = "text/x-script"; break; case ".hlp": retval = "application/hlp"; break; case ".hpg": retval = "application/vnd.hp-hpgl"; break; case ".hpgl": retval = "application/vnd.hp-hpgl"; break; case ".hqx": retval = "application/binhex"; break; case ".hta": retval = "application/hta"; break; case ".htc": retval = "text/x-component"; break; case ".htm": retval = "text/html"; break; case ".html": retval = "text/html"; break; case ".htmls": retval = "text/html"; break; case ".htt": retval = "text/webviewhtml"; break; case ".htx": retval = "text/html"; break; case ".ice": retval = "x-conference/x-cooltalk"; break; case ".ico": retval = "image/x-icon"; break; case ".idc": retval = "text/plain"; break; case ".ief": retval = "image/ief"; break; case ".iefs": retval = "image/ief"; break; case ".iges": retval = "application/iges"; break; case ".igs": retval = "application/iges"; break; case ".ima": retval = "application/x-ima"; break; case ".imap": retval = "application/x-httpd-imap"; break; case ".inf": retval = "application/inf"; break; case ".ins": retval = "application/x-internett-signup"; break; case ".ip": retval = "application/x-ip2"; break; case ".isu": retval = "video/x-isvideo"; break; case ".it": retval = "audio/it"; break; case ".iv": retval = "application/x-inventor"; break; case ".ivr": retval = "i-world/i-vrml"; break; case ".ivy": retval = "application/x-livescreen"; break; case ".jam": retval = "audio/x-jam"; break; case ".jav": retval = "text/plain"; break; case ".java": retval = "text/plain"; break; case ".jcm": retval = "application/x-java-commerce"; break; case ".jfif": retval = "image/jpeg"; break; case ".jfif-tbnl": retval = "image/jpeg"; break; case ".jpe": retval = "image/jpeg"; break; case ".jpeg": retval = "image/jpeg"; break; case ".jpg": retval = "image/jpeg"; break; case ".jps": retval = "image/x-jps"; break; case ".js": retval = "application/x-javascript"; break; case ".jut": retval = "image/jutvision"; break; case ".kar": retval = "audio/midi"; break; case ".ksh": retval = "application/x-ksh"; break; case ".la": retval = "audio/nspaudio"; break; case ".lam": retval = "audio/x-liveaudio"; break; case ".latex": retval = "application/x-latex"; break; case ".lha": retval = "application/octet-stream"; break; case ".lhx": retval = "application/octet-stream"; break; case ".list": retval = "text/plain"; break; case ".lma": retval = "audio/nspaudio"; break; case ".log": retval = "text/plain"; break; case ".lsp": retval = "application/x-lisp"; break; case ".lst": retval = "text/plain"; break; case ".lsx": retval = "text/x-la-asf"; break; case ".ltx": retval = "application/x-latex"; break; case ".lzh": retval = "application/octet-stream"; break; case ".lzx": retval = "application/octet-stream"; break; case ".m": retval = "text/plain"; break; case ".m1v": retval = "video/mpeg"; break; case ".m2a": retval = "audio/mpeg"; break; case ".m2v": retval = "video/mpeg"; break; case ".m3u": retval = "audio/x-mpequrl"; break; case ".man": retval = "application/x-troff-man"; break; case ".map": retval = "application/x-navimap"; break; case ".mar": retval = "text/plain"; break; case ".mbd": retval = "application/mbedlet"; break; case ".mc$": retval = "application/x-magic-cap-package-1.0"; break; case ".mcd": retval = "application/mcad"; break; case ".mcf": retval = "text/mcf"; break; case ".mcp": retval = "application/netmc"; break; case ".me": retval = "application/x-troff-me"; break; case ".mht": retval = "message/rfc822"; break; case ".mhtml": retval = "message/rfc822"; break; case ".mid": retval = "audio/midi"; break; case ".midi": retval = "audio/midi"; break; case ".mif": retval = "application/x-mif"; break; case ".mime": retval = "message/rfc822"; break; case ".mjf": retval = "audio/x-vnd.audioexplosion.mjuicemediafile"; break; case ".mjpg": retval = "video/x-motion-jpeg"; break; case ".mm": retval = "application/base64"; break; case ".mme": retval = "application/base64"; break; case ".mod": retval = "audio/mod"; break; case ".moov": retval = "video/quicktime"; break; case ".mov": retval = "video/quicktime"; break; case ".movie": retval = "video/x-sgi-movie"; break; case ".mp2": retval = "audio/mpeg"; break; case ".mp3": retval = "audio/mpeg"; break; case ".mpa": retval = "audio/mpeg"; break; case ".mpc": retval = "application/x-project"; break; case ".mpe": retval = "video/mpeg"; break; case ".mpeg": retval = "video/mpeg"; break; case ".mpg": retval = "video/mpeg"; break; case ".mpga": retval = "audio/mpeg"; break; case ".mpp": retval = "application/vnd.ms-project"; break; case ".mpt": retval = "application/vnd.ms-project"; break; case ".mpv": retval = "application/vnd.ms-project"; break; case ".mpx": retval = "application/vnd.ms-project"; break; case ".mrc": retval = "application/marc"; break; case ".ms": retval = "application/x-troff-ms"; break; case ".mv": retval = "video/x-sgi-movie"; break; case ".my": retval = "audio/make"; break; case ".mzz": retval = "application/x-vnd.audioexplosion.mzz"; break; case ".nap": retval = "image/naplps"; break; case ".naplps": retval = "image/naplps"; break; case ".nc": retval = "application/x-netcdf"; break; case ".ncm": retval = "application/vnd.nokia.configuration-message"; break; case ".nif": retval = "image/x-niff"; break; case ".niff": retval = "image/x-niff"; break; case ".nix": retval = "application/x-mix-transfer"; break; case ".nsc": retval = "application/x-conference"; break; case ".nvd": retval = "application/x-navidoc"; break; case ".o": retval = "application/octet-stream"; break; case ".oda": retval = "application/oda"; break; case ".omc": retval = "application/x-omc"; break; case ".omcd": retval = "application/x-omcdatamaker"; break; case ".omcr": retval = "application/x-omcregerator"; break; case ".p": retval = "text/x-pascal"; break; case ".p10": retval = "application/pkcs10"; break; case ".p12": retval = "application/pkcs-12"; break; case ".p7a": retval = "application/x-pkcs7-signature"; break; case ".p7c": retval = "application/pkcs7-mime"; break; case ".p7m": retval = "application/pkcs7-mime"; break; case ".p7r": retval = "application/x-pkcs7-certreqresp"; break; case ".p7s": retval = "application/pkcs7-signature"; break; case ".part": retval = "application/pro_eng"; break; case ".pas": retval = "text/pascal"; break; case ".pbm": retval = "image/x-portable-bitmap"; break; case ".pcl": retval = "application/vnd.hp-pcl"; break; case ".pct": retval = "image/x-pict"; break; case ".pcx": retval = "image/x-pcx"; break; case ".pdb": retval = "chemical/x-pdb"; break; case ".pdf": retval = "application/pdf"; break; case ".pfunk": retval = "audio/make"; break; case ".pgm": retval = "image/x-portable-greymap"; break; case ".pic": retval = "image/pict"; break; case ".pict": retval = "image/pict"; break; case ".pkg": retval = "application/x-newton-compatible-pkg"; break; case ".pko": retval = "application/vnd.ms-pki.pko"; break; case ".pl": retval = "text/plain"; break; case ".plx": retval = "application/x-pixclscript"; break; case ".pm": retval = "image/x-xpixmap"; break; case ".pm4": retval = "application/x-pagemaker"; break; case ".pm5": retval = "application/x-pagemaker"; break; case ".png": retval = "image/png"; break; case ".pnm": retval = "application/x-portable-anymap"; break; case ".pot": retval = "application/vnd.ms-powerpoint"; break; case ".pov": retval = "model/x-pov"; break; case ".ppa": retval = "application/vnd.ms-powerpoint"; break; case ".ppm": retval = "image/x-portable-pixmap"; break; case ".pps": retval = "application/vnd.ms-powerpoint"; break; case ".ppt": retval = "application/vnd.ms-powerpoint"; break; case ".ppz": retval = "application/vnd.ms-powerpoint"; break; case ".pre": retval = "application/x-freelance"; break; case ".prt": retval = "application/pro_eng"; break; case ".ps": retval = "application/postscript"; break; case ".psd": retval = "application/octet-stream"; break; case ".pvu": retval = "paleovu/x-pv"; break; case ".pwz": retval = "application/vnd.ms-powerpoint"; break; case ".py": retval = "text/x-script.phyton"; break; case ".pyc": retval = "applicaiton/x-bytecode.python"; break; case ".qcp": retval = "audio/vnd.qcelp"; break; case ".qd3": retval = "x-world/x-3dmf"; break; case ".qd3d": retval = "x-world/x-3dmf"; break; case ".qif": retval = "image/x-quicktime"; break; case ".qt": retval = "video/quicktime"; break; case ".qtc": retval = "video/x-qtc"; break; case ".qti": retval = "image/x-quicktime"; break; case ".qtif": retval = "image/x-quicktime"; break; case ".ra": retval = "audio/x-pn-realaudio"; break; case ".ram": retval = "audio/x-pn-realaudio"; break; case ".ras": retval = "application/x-cmu-raster"; break; case ".rast": retval = "image/cmu-raster"; break; case ".rexx": retval = "text/x-script.rexx"; break; case ".rf": retval = "image/vnd.rn-realflash"; break; case ".rgb": retval = "image/x-rgb"; break; case ".rm": retval = "application/vnd.rn-realmedia"; break; case ".rmi": retval = "audio/mid"; break; case ".rmm": retval = "audio/x-pn-realaudio"; break; case ".rmp": retval = "audio/x-pn-realaudio"; break; case ".rng": retval = "application/ringing-tones"; break; case ".rnx": retval = "application/vnd.rn-realplayer"; break; case ".roff": retval = "application/x-troff"; break; case ".rp": retval = "image/vnd.rn-realpix"; break; case ".rpm": retval = "audio/x-pn-realaudio-plugin"; break; case ".rt": retval = "text/richtext"; break; case ".rtf": retval = "text/richtext"; break; case ".rtx": retval = "text/richtext"; break; case ".rv": retval = "video/vnd.rn-realvideo"; break; case ".s": retval = "text/x-asm"; break; case ".s3m": retval = "audio/s3m"; break; case ".saveme": retval = "application/octet-stream"; break; case ".sbk": retval = "application/x-tbook"; break; case ".scm": retval = "application/x-lotusscreencam"; break; case ".sdml": retval = "text/plain"; break; case ".sdp": retval = "application/sdp"; break; case ".sdr": retval = "application/sounder"; break; case ".sea": retval = "application/sea"; break; case ".set": retval = "application/set"; break; case ".sgm": retval = "text/sgml"; break; case ".sgml": retval = "text/sgml"; break; case ".sh": retval = "application/x-sh"; break; case ".shar": retval = "application/x-shar"; break; case ".shtml": retval = "text/html"; break; case ".sid": retval = "audio/x-psid"; break; case ".sit": retval = "application/x-sit"; break; case ".skd": retval = "application/x-koan"; break; case ".skm": retval = "application/x-koan"; break; case ".skp": retval = "application/x-koan"; break; case ".skt": retval = "application/x-koan"; break; case ".sl": retval = "application/x-seelogo"; break; case ".smi": retval = "application/smil"; break; case ".smil": retval = "application/smil"; break; case ".snd": retval = "audio/basic"; break; case ".sol": retval = "application/solids"; break; case ".spc": retval = "text/x-speech"; break; case ".spl": retval = "application/futuresplash"; break; case ".spr": retval = "application/x-sprite"; break; case ".sprite": retval = "application/x-sprite"; break; case ".src": retval = "application/x-wais-source"; break; case ".ssi": retval = "text/x-server-parsed-html"; break; case ".ssm": retval = "application/streamingmedia"; break; case ".sst": retval = "application/vnd.ms-pki.certstore"; break; case ".step": retval = "application/step"; break; case ".stl": retval = "application/sla"; break; case ".stp": retval = "application/step"; break; case ".sv4cpio": retval = "application/x-sv4cpio"; break; case ".sv4crc": retval = "application/x-sv4crc"; break; case ".svf": retval = "image/vnd.dwg"; break; case ".svr": retval = "application/x-world"; break; case ".swf": retval = "application/x-shockwave-flash"; break; case ".t": retval = "application/x-troff"; break; case ".talk": retval = "text/x-speech"; break; case ".tar": retval = "application/x-tar"; break; case ".tbk": retval = "application/toolbook"; break; case ".tcl": retval = "application/x-tcl"; break; case ".tcsh": retval = "text/x-script.tcsh"; break; case ".tex": retval = "application/x-tex"; break; case ".texi": retval = "application/x-texinfo"; break; case ".texinfo": retval = "application/x-texinfo"; break; case ".text": retval = "text/plain"; break; case ".tgz": retval = "application/x-compressed"; break; case ".tif": retval = "image/tiff"; break; case ".tiff": retval = "image/tiff"; break; case ".tr": retval = "application/x-troff"; break; case ".tsi": retval = "audio/tsp-audio"; break; case ".tsp": retval = "application/dsptype"; break; case ".tsv": retval = "text/tab-separated-values"; break; case ".turbot": retval = "image/florian"; break; case ".txt": retval = "text/plain"; break; case ".uil": retval = "text/x-uil"; break; case ".uni": retval = "text/uri-list"; break; case ".unis": retval = "text/uri-list"; break; case ".unv": retval = "application/i-deas"; break; case ".uri": retval = "text/uri-list"; break; case ".uris": retval = "text/uri-list"; break; case ".ustar": retval = "application/x-ustar"; break; case ".uu": retval = "application/octet-stream"; break; case ".uue": retval = "text/x-uuencode"; break; case ".vcd": retval = "application/x-cdlink"; break; case ".vcs": retval = "text/x-vcalendar"; break; case ".vda": retval = "application/vda"; break; case ".vdo": retval = "video/vdo"; break; case ".vew": retval = "application/groupwise"; break; case ".viv": retval = "video/vivo"; break; case ".vivo": retval = "video/vivo"; break; case ".vmd": retval = "application/vocaltec-media-desc"; break; case ".vmf": retval = "application/vocaltec-media-file"; break; case ".voc": retval = "audio/voc"; break; case ".vos": retval = "video/vosaic"; break; case ".vox": retval = "audio/voxware"; break; case ".vqe": retval = "audio/x-twinvq-plugin"; break; case ".vqf": retval = "audio/x-twinvq"; break; case ".vql": retval = "audio/x-twinvq-plugin"; break; case ".vrml": retval = "application/x-vrml"; break; case ".vrt": retval = "x-world/x-vrt"; break; case ".vsd": retval = "application/x-visio"; break; case ".vst": retval = "application/x-visio"; break; case ".vsw": retval = "application/x-visio"; break; case ".w60": retval = "application/wordperfect6.0"; break; case ".w61": retval = "application/wordperfect6.1"; break; case ".w6w": retval = "application/msword"; break; case ".wav": retval = "audio/wav"; break; case ".wb1": retval = "application/x-qpro"; break; case ".wbmp": retval = "image/vnd.wap.wbmp"; break; case ".web": retval = "application/vnd.xara"; break; case ".wiz": retval = "application/msword"; break; case ".wk1": retval = "application/x-123"; break; case ".wmf": retval = "windows/metafile"; break; case ".wml": retval = "text/vnd.wap.wml"; break; case ".wmlc": retval = "application/vnd.wap.wmlc"; break; case ".wmls": retval = "text/vnd.wap.wmlscript"; break; case ".wmlsc": retval = "application/vnd.wap.wmlscriptc"; break; case ".word": retval = "application/msword"; break; case ".wp": retval = "application/wordperfect"; break; case ".wp5": retval = "application/wordperfect"; break; case ".wp6": retval = "application/wordperfect"; break; case ".wpd": retval = "application/wordperfect"; break; case ".wq1": retval = "application/x-lotus"; break; case ".wri": retval = "application/mswrite"; break; case ".wrl": retval = "application/x-world"; break; case ".wrz": retval = "x-world/x-vrml"; break; case ".wsc": retval = "text/scriplet"; break; case ".wsrc": retval = "application/x-wais-source"; break; case ".wtk": retval = "application/x-wintalk"; break; case ".xbm": retval = "image/x-xbitmap"; break; case ".xdr": retval = "video/x-amt-demorun"; break; case ".xgz": retval = "xgl/drawing"; break; case ".xif": retval = "image/vnd.xiff"; break; case ".xl": retval = "application/excel"; break; case ".xla": retval = "application/vnd.ms-excel"; break; case ".xlb": retval = "application/vnd.ms-excel"; break; case ".xlc": retval = "application/vnd.ms-excel"; break; case ".xld": retval = "application/vnd.ms-excel"; break; case ".xlk": retval = "application/vnd.ms-excel"; break; case ".xll": retval = "application/vnd.ms-excel"; break; case ".xlm": retval = "application/vnd.ms-excel"; break; case ".xls": retval = "application/vnd.ms-excel"; break; case ".xlt": retval = "application/vnd.ms-excel"; break; case ".xlv": retval = "application/vnd.ms-excel"; break; case ".xlw": retval = "application/vnd.ms-excel"; break; case ".xm": retval = "audio/xm"; break; case ".xml": retval = "application/xml"; break; case ".xmz": retval = "xgl/movie"; break; case ".xpix": retval = "application/x-vnd.ls-xpix"; break; case ".xpm": retval = "image/xpm"; break; case ".x-png": retval = "image/png"; break; case ".xsr": retval = "video/x-amt-showrun"; break; case ".xwd": retval = "image/x-xwd"; break; case ".xyz": retval = "chemical/x-pdb"; break; case ".z": retval = "application/x-compressed"; break; case ".zip": retval = "application/zip"; break; case ".zoo": retval = "application/octet-stream"; break; case ".zsh": retval = "text/x-script.zsh"; break; default : retval="application/octet-stream"; break; } return retval; }

最后找到合适的方法：

最终代码：

/// <summary> /// 根据文件名来获取对应的"输出流的HTTP MIME"类型 /// </summary> /// <param name="Filename">文件名</param> /// <returns></returns> public string MimeType(string Filename) { string mime = string.Empty; string ext = System.IO.Path.GetExtension(Filename).ToLower(); switch (ext) { case ".zip": case ".rar": mime = "application/x-zip-compressed"; break; default: Microsoft.Win32.RegistryKey rk = Microsoft.Win32.Registry.ClassesRoot.OpenSubKey(ext); if (rk != null && rk.GetValue("Content Type") != null) mime = rk.GetValue("Content Type").ToString(); break; } return mime; } Response.Clear(); string strType = MimeType(fileName); if (!string.IsNullOrEmpty(strType)) Response.ContentType = strType; Response.AddHeader("Content-Disposition", "attachment;filename=" + fileName); Response.TransmitFile(tempdir); Response.Write("<mce:script language:javascript></mce:script>"); Response.End();

参考：http://www.microsoft.com/china/msdn/library/webservices/asp.net/WebDownloads.mspx?mfr=true

http://www.debugging.com/bug/13927