How can I determine the length (i.e. duration) of a .wav file in C#?

Question

In the uncompressed situation I know I need to read the wav header, pull out the number of channels, bits, and sample rate and work it out from there: (channels) * (bits) *

Answer 1

Not to take anything away from the answer already accepted, but I was able to get the duration of an audio file (several different formats, including AC3, which is what I needed at the time) using the Microsoft.DirectX.AudioVideoPlayBack namespace. This is part of DirectX 9.0 for Managed Code. Adding a reference to that made my code as simple as this...

Public Shared Function GetDuration(ByVal Path As String) As Integer
    If File.Exists(Path) Then
        Return CInt(New Audio(Path, False).Duration)
    Else
        Throw New FileNotFoundException("Audio File Not Found: " & Path)
    End If
End Function

And it's pretty fast, too! Here's a reference for the Audio class.