在ASP.NET中使用如下方式，保存文件。下面例子，保存一个excel文件。

            Response.ContentType = @"application/x-xls";


            Response.AppendHeader("Content-Disposition", "attachment; filename=" + @"\test.xls");


            //此处将内容写入文件，例如
            Response.Flush();


            //Response.WriteFile("存有内容的文件", true);


            //Response.Write(参数);


            Response.End();

".*"="application/octet-stream"
            ".001"="application/x-001"
            ".301"="application/x-301"
            ".323"="text/h323"
            ".906"="application/x-906"
            ".907"="drawing/907"
            ".a11"="application/x-a11"
            ".acp"="audio/x-mei-aac"
            ".ai"="application/postscript"
            ".aif"="audio/aiff"
            ".aifc"="audio/aiff"
            ".aiff"="audio/aiff"
            ".anv"="application/x-anv"
            ".asa"="text/asa"
            ".asf"="video/x-ms-asf"
            ".asp"="text/asp"
            ".asx"="video/x-ms-asf"
            ".au"="audio/basic"
            ".avi"="video/avi"
            ".awf"="application/vnd.adobe.workflow"
            ".biz"="text/xml"
            ".bmp"="application/x-bmp"
            ".bot"="application/x-bot"
            ".c4t"="application/x-c4t"
            ".c90"="application/x-c90"
            ".cal"="application/x-cals"
            ".cat"="application/vnd.ms-pki.seccat"
            ".cdf"="application/x-netcdf"
            ".cdr"="application/x-cdr"
            ".cel"="application/x-cel"
            ".cer"="application/x-x509-ca-cert"
            ".cg4"="application/x-g4"
            ".cgm"="application/x-cgm"
            ".cit"="application/x-cit"
            ".class"="java/*"
            ".cml"="text/xml"
            ".cmp"="application/x-cmp"
            ".cmx"="application/x-cmx"
            ".cot"="application/x-cot"
            ".crl"="application/pkix-crl"
            ".crt"="application/x-x509-ca-cert"
            ".csi"="application/x-csi"
            ".css"="text/css"
            ".cut"="application/x-cut"
            ".dbf"="application/x-dbf"
            ".dbm"="application/x-dbm"
            ".dbx"="application/x-dbx"
            ".dcd"="text/xml"
            ".dcx"="application/x-dcx"
            ".der"="application/x-x509-ca-cert"
            ".dgn"="application/x-dgn"
            ".dib"="application/x-dib"
            ".dll"="application/x-msdownload"
            ".doc"="application/msword"
            ".dot"="application/msword"
            ".drw"="application/x-drw"
            ".dtd"="text/xml"
            ".dwf"="Model/vnd.dwf"
            ".dwf"="application/x-dwf"
            ".dwg"="application/x-dwg"
            ".dxb"="application/x-dxb"
            ".dxf"="application/x-dxf"
            ".edn"="application/vnd.adobe.edn"
            ".emf"="application/x-emf"
            ".eml"="message/rfc822"
            ".ent"="text/xml"
            ".epi"="application/x-epi"
            ".eps"="application/x-ps"
            ".eps"="application/postscript"
            ".etd"="application/x-ebx"
            ".exe"="application/x-msdownload"
            ".fax"="image/fax"
            ".fdf"="application/vnd.fdf"
            ".fif"="application/fractals"
            ".fo"="text/xml"
            ".frm"="application/x-frm"
            ".g4"="application/x-g4"
            ".gbr"="application/x-gbr"
            ".gcd"="application/x-gcd"
            ".gif"="image/gif"
            ".gl2"="application/x-gl2"
            ".gp4"="application/x-gp4"
            ".hgl"="application/x-hgl"
            ".hmr"="application/x-hmr"
            ".hpg"="application/x-hpgl"
            ".hpl"="application/x-hpl"
            ".hqx"="application/mac-binhex40"
            ".hrf"="application/x-hrf"
            ".hta"="application/hta"
            ".htc"="text/x-component"
            ".htm"="text/html"
            ".html"="text/html"
            ".htt"="text/webviewhtml"
            ".htx"="text/html"
            ".icb"="application/x-icb"
            ".ico"="image/x-icon"
            ".ico"="application/x-ico"
            ".iff"="application/x-iff"
            ".ig4"="application/x-g4"
            ".igs"="application/x-igs"
            ".iii"="application/x-iphone"
            ".img"="application/x-img"
            ".ins"="application/x-internet-signup"
            ".isp"="application/x-internet-signup"
            ".IVF"="video/x-ivf"
            ".java"="java/*"
            ".jfif"="image/jpeg"
            ".jpe"="image/jpeg"
            ".jpe"="application/x-jpe"
            ".jpeg"="image/jpeg"
            ".jpg"="image/jpeg"
            ".jpg"="application/x-jpg"
            ".js"="application/x-javascript"
            ".jsp"="text/html"
            ".la1"="audio/x-liquid-file"
            ".lar"="application/x-laplayer-reg"
            ".latex"="application/x-latex"
            ".lavs"="audio/x-liquid-secure"
            ".lbm"="application/x-lbm"
            ".lmsff"="audio/x-la-lms"
            ".ls"="application/x-javascript"
            ".ltr"="application/x-ltr"
            ".m1v"="video/x-mpeg"
            ".m2v"="video/x-mpeg"
            ".m3u"="audio/mpegurl"
            ".m4e"="video/mpeg4"
            ".mac"="application/x-mac"
            ".man"="application/x-troff-man"
            ".math"="text/xml"
            ".mdb"="application/msaccess"
            ".mdb"="application/x-mdb"
            ".mfp"="application/x-shockwave-flash"
            ".mht"="message/rfc822"
            ".mhtml"="message/rfc822"
            ".mi"="application/x-mi"
            ".mid"="audio/mid"
            ".midi"="audio/mid"
            ".mil"="application/x-mil"
            ".mml"="text/xml"
            ".mnd"="audio/x-musicnet-download"
            ".mns"="audio/x-musicnet-stream"
            ".mocha"="application/x-javascript"
            ".movie"="video/x-sgi-movie"
            ".mp1"="audio/mp1"
            ".mp2"="audio/mp2"
            ".mp2v"="video/mpeg"
            ".mp3"="audio/mp3"
            ".mp4"="video/mpeg4"
            ".mpa"="video/x-mpg"
            ".mpd"="application/vnd.ms-project"
            ".mpe"="video/x-mpeg"
            ".mpeg"="video/mpg"
            ".mpg"="video/mpg"
            ".mpga"="audio/rn-mpeg"
            ".mpp"="application/vnd.ms-project"
            ".mps"="video/x-mpeg"
            ".mpt"="application/vnd.ms-project"
            ".mpv"="video/mpg"
            ".mpv2"="video/mpeg"
            ".mpw"="application/vnd.ms-project"
            ".mpx"="application/vnd.ms-project"
            ".mtx"="text/xml"
            ".mxp"="application/x-mmxp"
            ".net"="image/pnetvue"
            ".nrf"="application/x-nrf"
            ".nws"="message/rfc822"
            ".odc"="text/x-ms-odc"
            ".out"="application/x-out"
            ".p10"="application/pkcs10"
            ".p12"="application/x-pkcs12"
            ".p7b"="application/x-pkcs7-certificates"
            ".p7c"="application/pkcs7-mime"
            ".p7m"="application/pkcs7-mime"
            ".p7r"="application/x-pkcs7-certreqresp"
            ".p7s"="application/pkcs7-signature"
            ".pc5"="application/x-pc5"
            ".pci"="application/x-pci"
            ".pcl"="application/x-pcl"
            ".pcx"="application/x-pcx"
            ".pdf"="application/pdf"
            ".pdf"="application/pdf"
            ".pdx"="application/vnd.adobe.pdx"
            ".pfx"="application/x-pkcs12"
            ".pgl"="application/x-pgl"
            ".pic"="application/x-pic"
            ".pko"="application/vnd.ms-pki.pko"
            ".pl"="application/x-perl"
            ".plg"="text/html"
            ".pls"="audio/scpls"
            ".plt"="application/x-plt"
            ".png"="image/png"
            ".png"="application/x-png"
            ".pot"="application/vnd.ms-powerpoint"
            ".ppa"="application/vnd.ms-powerpoint"
            ".ppm"="application/x-ppm"
            ".pps"="application/vnd.ms-powerpoint"
            ".ppt"="application/vnd.ms-powerpoint"
            ".ppt"="application/x-ppt"
            ".pr"="application/x-pr"
            ".prf"="application/pics-rules"
            ".prn"="application/x-prn"
            ".prt"="application/x-prt"
            ".ps"="application/x-ps"
            ".ps"="application/postscript"
            ".ptn"="application/x-ptn"
            ".pwz"="application/vnd.ms-powerpoint"
            ".r3t"="text/vnd.rn-realtext3d"
            ".ra"="audio/vnd.rn-realaudio"
            ".ram"="audio/x-pn-realaudio"
            ".ras"="application/x-ras"
            ".rat"="application/rat-file"
            ".rdf"="text/xml"
            ".rec"="application/vnd.rn-recording"
            ".red"="application/x-red"
            ".rgb"="application/x-rgb"
            ".rjs"="application/vnd.rn-realsystem-rjs"
            ".rjt"="application/vnd.rn-realsystem-rjt"
            ".rlc"="application/x-rlc"
            ".rle"="application/x-rle"
            ".rm"="application/vnd.rn-realmedia"
            ".rmf"="application/vnd.adobe.rmf"
            ".rmi"="audio/mid"
            ".rmj"="application/vnd.rn-realsystem-rmj"
            ".rmm"="audio/x-pn-realaudio"
            ".rmp"="application/vnd.rn-rn_music_package"
            ".rms"="application/vnd.rn-realmedia-secure"
            ".rmvb"="application/vnd.rn-realmedia-vbr"
            ".rmx"="application/vnd.rn-realsystem-rmx"
            ".rnx"="application/vnd.rn-realplayer"
            ".rp"="image/vnd.rn-realpix"
            ".rpm"="audio/x-pn-realaudio-plugin"
            ".rsml"="application/vnd.rn-rsml"
            ".rt"="text/vnd.rn-realtext"
            ".rtf"="application/msword"
            ".rtf"="application/x-rtf"
            ".rv"="video/vnd.rn-realvideo"
            ".sam"="application/x-sam"
            ".sat"="application/x-sat"
            ".sdp"="application/sdp"
            ".sdw"="application/x-sdw"
            ".sit"="application/x-stuffit"
            ".slb"="application/x-slb"
            ".sld"="application/x-sld"
            ".slk"="drawing/x-slk"
            ".smi"="application/smil"
            ".smil"="application/smil"
            ".smk"="application/x-smk"
            ".snd"="audio/basic"
            ".sol"="text/plain"
            ".sor"="text/plain"
            ".spc"="application/x-pkcs7-certificates"
            ".spl"="application/futuresplash"
            ".spp"="text/xml"
            ".ssm"="application/streamingmedia"
            ".sst"="application/vnd.ms-pki.certstore"
            ".stl"="application/vnd.ms-pki.stl"
            ".stm"="text/html"
            ".sty"="application/x-sty"
            ".svg"="text/xml"
            ".swf"="application/x-shockwave-flash"
            ".tdf"="application/x-tdf"
            ".tg4"="application/x-tg4"
            ".tga"="application/x-tga"
            ".tif"="image/tiff"
            ".tif"="application/x-tif"
            ".tiff"="image/tiff"
            ".tld"="text/xml"
            ".top"="drawing/x-top"
            ".torrent"="application/x-bittorrent"
            ".tsd"="text/xml"
            ".txt"="text/plain"
            ".uin"="application/x-icq"
            ".uls"="text/iuls"
            ".vcf"="text/x-vcard"
            ".vda"="application/x-vda"
            ".vdx"="application/vnd.visio"
            ".vml"="text/xml"
            ".vpg"="application/x-vpeg005"
            ".vsd"="application/vnd.visio"
            ".vsd"="application/x-vsd"
            ".vss"="application/vnd.visio"
            ".vst"="application/vnd.visio"
            ".vst"="application/x-vst"
            ".vsw"="application/vnd.visio"
            ".vsx"="application/vnd.visio"
            ".vtx"="application/vnd.visio"
            ".vxml"="text/xml"
            ".wav"="audio/wav"
            ".wax"="audio/x-ms-wax"
            ".wb1"="application/x-wb1"
            ".wb2"="application/x-wb2"
            ".wb3"="application/x-wb3"
            ".wbmp"="image/vnd.wap.wbmp"
            ".wiz"="application/msword"
            ".wk3"="application/x-wk3"
            ".wk4"="application/x-wk4"
            ".wkq"="application/x-wkq"
            ".wks"="application/x-wks"
            ".wm"="video/x-ms-wm"
            ".wma"="audio/x-ms-wma"
            ".wmd"="application/x-ms-wmd"
            ".wmf"="application/x-wmf"
            ".wml"="text/vnd.wap.wml"
            ".wmv"="video/x-ms-wmv"
            ".wmx"="video/x-ms-wmx"
            ".wmz"="application/x-ms-wmz"
            ".wp6"="application/x-wp6"
            ".wpd"="application/x-wpd"
            ".wpg"="application/x-wpg"
            ".wpl"="application/vnd.ms-wpl"
            ".wq1"="application/x-wq1"
            ".wr1"="application/x-wr1"
            ".wri"="application/x-wri"
            ".wrk"="application/x-wrk"
            ".ws"="application/x-ws"
            ".ws2"="application/x-ws"
            ".wsc"="text/scriptlet"
            ".wsdl"="text/xml"
            ".wvx"="video/x-ms-wvx"
            ".xdp"="application/vnd.adobe.xdp"
            ".xdr"="text/xml"
            ".xfd"="application/vnd.adobe.xfd"
            ".xfdf"="application/vnd.adobe.xfdf"
            ".xhtml"="text/html"
            ".xls"="application/vnd.ms-excel"
            ".xls"="application/x-xls"
            ".xlw"="application/x-xlw"
            ".xml"="text/xml"
            ".xpl"="audio/scpls"
            ".xq"="text/xml"
            ".xql"="text/xml"
            ".xquery"="text/xml"
            ".xsd"="text/xml"
            ".xsl"="text/xml"
            ".xslt"="text/xml"
            ".xwd"="application/x-xwd"
            ".x_b"="application/x-x_b"
            ".x_t"="application/x-x_t"

ASP.NET—016：ASP.NET中保存文件对话框