参见： http://***.com/questions/58510/using -net-how-you-you-the-mime-type-of-a-file-on-the-file-signature / 58570＃58570 [ ^ ]

请检查此...

http://***.com/questions/1437382/get-file-type-in​​-net [ ^ ]

please check this...
http://***.com/questions/1437382/get-file-type-in-net[^]

您好


看你可以用这个

Hi
see you can use this

string p = @"C:\Test.txt";
string e = Path.GetExtension(p);

结果：e =txt

Result : e= "txt"