Field Value

Type: String
A string containing the extension of the file including the ".". If the file name does not have extension information, GetExtension returns string.Empty.

The extension of the file name is obtained by searching it for a period (.), starting with the last character and continuing toward the start. If a period is found before a DirectorySeparatorChar or AltDirectorySeparatorChar character, the returned string contains the period and the characters after it; otherwise, string.Empty is returned.