>Hello Team,
>
>I have a restricted folder that i am allowing authorized downloading from through a response.binarywrite fairly straight forward stuff. What I would like to do is get the content type for the file server side before I try to do the write. So i can set my Response.ContentType = "xx" correct without relying on the file extension and a big switch statement.
>
>My humble thanks in advance,

Ok I have the solution for those of you who are interested. For your coding pleasure I have expanded it in a manner that requires no using statements. urlmon.dll is part of IE

Joe.

[System.Runtime.InteropServices.DllImport("urlmon.dll", CharSet = System.Runtime.InteropServices.CharSet.Unicode, ExactSpelling = true, SetLastError = false)] 
static extern int FindMimeFromData(IntPtr pBC, 
[System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPWStr)] string pwzUrl,
[System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPArray, ArraySubType = System.Runtime.InteropServices.UnmanagedType.I1, SizeParamIndex = 3)] 
 byte[] pBuffer, int cbSize,
[System.Runtime.InteropServices.MarshalAs(System.Runtime.InteropServices.UnmanagedType.LPWStr)] string pwzMimeProposed, int dwMimeFlags, out IntPtr ppwzMimeOut, int dwReserved);    
    
    /// <summary>
    /// Ensures that file exists and retrieves the content type 
    /// </summary>
    /// <param name="strfileName"></param>
    /// <returns>Returns the Content MimeType </returns>
    public static string getMimeFromFile(string strFileName)
    {
        IntPtr mimeout;
        if (!System.IO.File.Exists(strFileName))
            throw new System.IO.FileNotFoundException(strFileName + " not found");

        int MaxContent = (int)new System.IO.FileInfo(strFileName).Length;
        if (MaxContent > 4096) MaxContent = 4096;
        System.IO.FileStream fs = System.IO.File.OpenRead(strFileName);


        byte[] buf = new byte[MaxContent];
        fs.Read(buf, 0, MaxContent);
        fs.Close();
        int result = FindMimeFromData(IntPtr.Zero, strFileName, buf, MaxContent, null, 0, out mimeout, 0);

        if (result != 0)
            throw System.Runtime.InteropServices.Marshal.GetExceptionForHR(result);

        string mime = System.Runtime.InteropServices.Marshal.PtrToStringUni(mimeout);
        System.Runtime.InteropServices.Marshal.FreeCoTaskMem(mimeout);
        return mime;
    }
    //rename crystal.jpg to .gif to test functionality!
    //string getImg = Environment.GetEnvironmentVariable("windir") + "\\Web\\WallPaper\\Crystal.gif";
    //string mime = getMimeFromFile(getImg);