string extension; 

extension = extension.ToUpper(); 

string contentType;

if(extension == "*") 

 contentType = "application/octet-stream"; 

else if(extension == "323") 

 contentType = "text/h323"; 

else if(extension == "ACX") 

 contentType = "application/internet-property-stream"; 

else if(extension == "AI") 

 contentType = "application/postscript"; 

else if(extension == "AIF") 

 contentType = "audio/x-aiff"; 

else if(extension == "AIFC") 

 contentType = "audio/x-aiff"; 

else if(extension == "AIFF") 

 contentType = "audio/x-aiff"; 

else if(extension == "ASF") 

 contentType = "video/x-ms-asf"; 

else if(extension == "SR") 

 contentType = "video/x-ms-asf"; 

else if(extension == "SX") 

 contentType = "video/x-ms-asf"; 

else if(extension == "AU") 

 contentType = "audio/basic"; 

else if(extension == "AVI") 

 contentType = "video/x-msvideo"; 

else if(extension == "AXS") 

 contentType = "application/olescript"; 

else if(extension == "BAS") 

 contentType = "text/plain"; 

else if(extension == "BCPIO") 

 contentType = "application/x-bcpio"; 

else if(extension == "BIN") 

 contentType = "application/octet-stream"; 

else if(extension == "BMP") 

 contentType = "image/bmp"; 

else if(extension == "C") 

 contentType = "text/plain"; 

else if(extension == "CAT") 

 contentType = "application/vnd.ms-pkiseccat"; 

else if(extension == "CDF") 

 contentType = "application/x-cdf"; 

else if(extension == "CER") 

 contentType = "application/x-x509-ca-cert"; 

else if(extension == "CLASS") 

 contentType = "application/octet-stream"; 

else if(extension == "CLP") 

 contentType = "application/x-msclip"; 

else if(extension == "CMX") 

 contentType = "image/x-cmx"; 

else if(extension == "COD") 

 contentType = "image/cis-cod"; 

else if(extension == "CPIO") 

 contentType = "application/x-cpio"; 

else if(extension == "CRD") 

 contentType = "application/x-mscardfile"; 

else if(extension == "CRL") 

 contentType = "application/pkix-crl"; 

else if(extension == "CRT") 

 contentType = "application/x-x509-ca-cert"; 

else if(extension == "CSH") 

 contentType = "application/x-csh"; 

else if(extension == "CSS") 

 contentType = "text/css"; 

else if(extension == "DCR") 

 contentType = "application/x-director"; 

else if(extension == "DER") 

 contentType = "application/x-x509-ca-cert"; 

else if(extension == "DIR") 

 contentType = "application/x-director"; 

else if(extension == "DLL") 

 contentType = "application/x-msdownload"; 

else if(extension == "DMS") 

 contentType = "application/octet-stream"; 

else if(extension == "DOC") 

 contentType = "application/msword"; 

else if(extension == "DOT") 

 contentType = "application/msword"; 

else if(extension == "DVI") 

 contentType = "application/x-dvi"; 

else if(extension == "DXR") 

 contentType = "application/x-director"; 

else if(extension == "EPS") 

 contentType = "application/postscript"; 

else if(extension == "ETX") 

 contentType = "text/x-setext"; 

else if(extension == "EVY") 

 contentType = "application/envoy"; 

else if(extension == "EXE") 

 contentType = "application/octet-stream"; 

else if(extension == "FIF") 

 contentType = "application/fractals"; 

else if(extension == "FLR") 

 contentType = "x-world/x-vrml"; 

else if(extension == "GIF") 

 contentType = "image/gif"; 

else if(extension == "GTAR") 

 contentType = "application/x-gtar"; 

else if(extension == "GZ") 

 contentType = "application/x-gzip"; 

else if(extension == "H") 

 contentType = "text/plain"; 

else if(extension == "HDF") 

 contentType = "application/x-hdf"; 

else if(extension == "HLP") 

 contentType = "application/winhlp"; 

else if(extension == "HQX") 

 contentType = "application/mac-binhex40"; 

else if(extension == "HTA") 

 contentType = "application/hta"; 

else if(extension == "HTC") 

 contentType = "text/x-component"; 

else if(extension == "HTM") 

 contentType = "text/html"; 

else if(extension == "HTML") 

 contentType = "text/html"; 

else if(extension == "HTT") 

 contentType = "text/webviewhtml"; 

else if(extension == "ICO") 

 contentType = "image/x-icon"; 

else if(extension == "IEF") 

 contentType = "image/ief"; 

else if(extension == "III") 

 contentType = "application/x-iphone"; 

else if(extension == "INS") 

 contentType = "application/x-internet-signup"; 

else if(extension == "ISP") 

 contentType = "application/x-internet-signup"; 

else if(extension == "JFIF") 

 contentType = "image/pipeg"; 

else if(extension == "JPE") 

 contentType = "image/jpeg"; 

else if(extension == "JPEG") 

 contentType = "image/jpeg"; 

else if(extension == "ZIP") 

 contentType = "application/x-zip-compressed"; 

else if(extension == "RAR") 

 contentType = "application/octet-stream";

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