How to get the length (duration) of a media File in C# on Windows 7

        internal enum PROPDESC_RELATIVEDESCRIPTION_TYPE

        {

            PDRDT_GENERAL,

            PDRDT_DATE,

            PDRDT_SIZE,

            PDRDT_COUNT,

            PDRDT_REVISION,

            PDRDT_LENGTH,

            PDRDT_DURATION,

            PDRDT_SPEED,

            PDRDT_RATE,

            PDRDT_RATING,

            PDRDT_PRIORITY

        }

        [DllImport("propsys.dll", CharSet = CharSet.Unicode, SetLastError = true)]

        internal static extern int PSGetNameFromPropertyKey(

            ref PropertyKey propkey,

            [Out, MarshalAs(UnmanagedType.LPWStr)] out string ppszCanonicalName

        );

        [DllImport("propsys.dll", CharSet = CharSet.Unicode, SetLastError = true)]

        internal static extern HRESULT PSGetPropertyDescription(

            ref PropertyKey propkey,

            ref Guid riid,

            [Out, MarshalAs(UnmanagedType.Interface)] out IPropertyDescription ppv

        );

        [DllImport("propsys.dll", CharSet = CharSet.Unicode, SetLastError = true)]

        internal static extern int PSGetPropertyKeyFromName(

            [In, MarshalAs(UnmanagedType.LPWStr)] string pszCanonicalName,

            out PropertyKey propkey

        );

namespace ConsoleApplication1

{

    using System;

    using Microsoft.WindowsAPICodePack.Shell;

    class Program

    {

        static void Main(string[] args)

        {

            if(args.Length < 1)

            {

                Console.WriteLine("Usage: ConsoleApplication1.exe [Filename to test]");

                return;

            }

            string file = args[0];

            ShellFile so = ShellFile.FromFilePath(file);

            double nanoseconds;

            double.TryParse(so.Properties.System.Media.Duration.Value.ToString(), out nanoseconds);

            Console.WriteLine("NanaoSeconds: {0}", nanoseconds);

            if (nanoseconds > 0)

            {

                double seconds = Convert100NanosecondsToMilliseconds(nanoseconds) / 1000;

                Console.WriteLine(seconds.ToString());

            }

        }

        public static double Convert100NanosecondsToMilliseconds(double nanoseconds)

        {

            // One million nanoseconds in 1 millisecond, but we are passing in 100ns units...

            return nanoseconds * 0.0001;

        }

    }

} 

        using System.Runtime.InteropServices;

        [DllImport("winmm.dll")]

        public static extern int mciSendString(string lpstrCommand, StringBuilder lpstrReturnString, int uReturnLength, int hwndCallback);

        [DllImport("winmm.dll")]

        private static extern int mciGetErrorString(int l1, StringBuilder s1, int l2);

        private void FindLength(string file)

        {

            string cmd = "open " + file + " alias voice1";

            StringBuilder mssg = new StringBuilder(255);

            int h = mciSendString(cmd, null, 0, 0);

            int i = mciSendString("set voice1 time format ms", null, 0, 0);

            int j = mciSendString("status voice1 length", mssg, mssg.Capacity, 0);

            Console.WriteLine(mssg.ToString());

        }