c# - 如何获得 .m4v 格式的电影的运行时间？

Question

如何使用 C# .NET 获得电影的运行时间（在我的情况下为 .m4v）？

我不确定为此使用什么 API。

Answer 1

我在一些项目中所做的方式是使用 MediaInfo 库：链接在这里

使用系统；使用 System.Runtime.InteropServices；

namespace MediaInfoLib
{
    public enum StreamKind
    {
        General,
        Video,
        Audio,
        Text,
        Chapters,
        Image
    }

    public enum InfoKind
    {
        Name,
        Text,
        Measure,
        Options,
        NameText,
        MeasureText,
        Info,
        HowTo
    }

    public enum InfoOptions
    {
        ShowInInform,
        Support,
        ShowInSupported,
        TypeOfValue
    }

    public enum InfoFileOptions
    {
        FileOption_Nothing      = 0x00,
        FileOption_NoRecursive  = 0x01,
        FileOption_CloseAll     = 0x02,
        FileOption_Max          = 0x04
    };


    public class MediaInfo
    {
        //Import of DLL functions. DO NOT USE until you know what you do (MediaInfo DLL do NOT use CoTaskMemAlloc to allocate memory)  
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_New();
        [DllImport("MediaInfo.dll")]
        private static extern void   MediaInfo_Delete(IntPtr Handle);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_Open(IntPtr Handle, [MarshalAs(UnmanagedType.LPWStr)] string FileName);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfoA_Open(IntPtr Handle, IntPtr FileName);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_Open_Buffer_Init(IntPtr Handle, Int64 File_Size, Int64 File_Offset);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfoA_Open(IntPtr Handle, Int64 File_Size, Int64 File_Offset);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_Open_Buffer_Continue(IntPtr Handle, IntPtr Buffer, IntPtr Buffer_Size);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfoA_Open_Buffer_Continue(IntPtr Handle, Int64 File_Size, byte[] Buffer, IntPtr Buffer_Size);
        [DllImport("MediaInfo.dll")]
        private static extern Int64  MediaInfo_Open_Buffer_Continue_GoTo_Get(IntPtr Handle);
        [DllImport("MediaInfo.dll")]
        private static extern Int64  MediaInfoA_Open_Buffer_Continue_GoTo_Get(IntPtr Handle);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_Open_Buffer_Finalize(IntPtr Handle);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfoA_Open_Buffer_Finalize(IntPtr Handle);
        [DllImport("MediaInfo.dll")]
        private static extern void   MediaInfo_Close(IntPtr Handle);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_Inform(IntPtr Handle, IntPtr Reserved);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfoA_Inform(IntPtr Handle, IntPtr Reserved);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_GetI(IntPtr Handle, IntPtr StreamKind, IntPtr StreamNumber, IntPtr Parameter, IntPtr KindOfInfo);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfoA_GetI(IntPtr Handle, IntPtr StreamKind, IntPtr StreamNumber, IntPtr Parameter, IntPtr KindOfInfo);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_Get(IntPtr Handle, IntPtr StreamKind, IntPtr StreamNumber, [MarshalAs(UnmanagedType.LPWStr)] string Parameter, IntPtr KindOfInfo, IntPtr KindOfSearch);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfoA_Get(IntPtr Handle, IntPtr StreamKind, IntPtr StreamNumber, IntPtr Parameter, IntPtr KindOfInfo, IntPtr KindOfSearch);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_Option(IntPtr Handle, [MarshalAs(UnmanagedType.LPWStr)] string Option, [MarshalAs(UnmanagedType.LPWStr)] string Value);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfoA_Option(IntPtr Handle, IntPtr Option,  IntPtr Value);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_State_Get(IntPtr Handle);
        [DllImport("MediaInfo.dll")]
        private static extern IntPtr MediaInfo_Count_Get(IntPtr Handle, IntPtr StreamKind, IntPtr StreamNumber);

        //MediaInfo class
        public MediaInfo()
        {
            Handle = MediaInfo_New();
            if (Environment.OSVersion.ToString().IndexOf("Windows")==-1)
                MustUseAnsi=true;
            else
                MustUseAnsi=false;
        }
        ~MediaInfo() { MediaInfo_Delete(Handle); }
        public int Open(String FileName)
        {
            if (MustUseAnsi)
            {
                IntPtr FileName_Ptr = Marshal.StringToHGlobalAnsi(FileName);
                int ToReturn = (int)MediaInfoA_Open(Handle, FileName_Ptr);
                Marshal.FreeHGlobal(FileName_Ptr);
                return ToReturn;
            }
            else
                return (int)MediaInfo_Open(Handle, FileName);
        }
        public int Open_Buffer_Init(Int64 File_Size, Int64 File_Offset)
        {
            return (int)MediaInfo_Open_Buffer_Init(Handle, File_Size, File_Offset);
        }
        public int Open_Buffer_Continue(IntPtr Buffer, IntPtr Buffer_Size)
        {
            return (int)MediaInfo_Open_Buffer_Continue(Handle, Buffer, Buffer_Size);
        }
        public Int64 Open_Buffer_Continue_GoTo_Get()
        {
            return (int)MediaInfo_Open_Buffer_Continue_GoTo_Get(Handle);
        }
        public int Open_Buffer_Finalize()
        {
            return (int)MediaInfo_Open_Buffer_Finalize(Handle);
        }
        public void Close() { MediaInfo_Close(Handle); }
        public String Inform()
        {
            if (MustUseAnsi)
                return Marshal.PtrToStringAnsi(MediaInfoA_Inform(Handle, (IntPtr)0));
            else
                return Marshal.PtrToStringUni(MediaInfo_Inform(Handle, (IntPtr)0));
        }
        public String Get(StreamKind StreamKind, int StreamNumber, String Parameter, InfoKind KindOfInfo, InfoKind KindOfSearch)
        {
            if (MustUseAnsi)
            {
                IntPtr Parameter_Ptr=Marshal.StringToHGlobalAnsi(Parameter);
                String ToReturn=Marshal.PtrToStringAnsi(MediaInfoA_Get(Handle, (IntPtr)StreamKind, (IntPtr)StreamNumber, Parameter_Ptr, (IntPtr)KindOfInfo, (IntPtr)KindOfSearch));
                Marshal.FreeHGlobal(Parameter_Ptr);
                return ToReturn;
            }
            else
                return Marshal.PtrToStringUni(MediaInfo_Get(Handle, (IntPtr)StreamKind, (IntPtr)StreamNumber, Parameter, (IntPtr)KindOfInfo, (IntPtr)KindOfSearch));
        }
        public String Get(StreamKind StreamKind, int StreamNumber, int Parameter, InfoKind KindOfInfo)
        {
            if (MustUseAnsi)
                return Marshal.PtrToStringAnsi(MediaInfoA_GetI(Handle, (IntPtr)StreamKind, (IntPtr)StreamNumber, (IntPtr)Parameter, (IntPtr)KindOfInfo));
            else
                return Marshal.PtrToStringUni(MediaInfo_GetI(Handle, (IntPtr)StreamKind, (IntPtr)StreamNumber, (IntPtr)Parameter, (IntPtr)KindOfInfo));
        }
        public String Option(String Option, String Value)
        {
            if (MustUseAnsi)
            {
                IntPtr Option_Ptr=Marshal.StringToHGlobalAnsi(Option);
                IntPtr Value_Ptr=Marshal.StringToHGlobalAnsi(Value);
                String ToReturn=Marshal.PtrToStringAnsi(MediaInfoA_Option(Handle, Option_Ptr, Value_Ptr));
                Marshal.FreeHGlobal(Option_Ptr);
                Marshal.FreeHGlobal(Value_Ptr);
                return ToReturn;
            }
            else
                return Marshal.PtrToStringUni(MediaInfo_Option(Handle, Option, Value));
        }
        public int State_Get() { return (int)MediaInfo_State_Get(Handle); }
        public int Count_Get(StreamKind StreamKind, int StreamNumber) { return (int)MediaInfo_Count_Get(Handle, (IntPtr)StreamKind, (IntPtr)StreamNumber); }
        private IntPtr Handle;
        private bool MustUseAnsi;

        //Default values, if you know how to set default values in C#, say me
        public String Get(StreamKind StreamKind, int StreamNumber, String Parameter, InfoKind KindOfInfo) { return Get(StreamKind, StreamNumber, Parameter, KindOfInfo, InfoKind.Name); }
        public String Get(StreamKind StreamKind, int StreamNumber, String Parameter) { return Get(StreamKind, StreamNumber, Parameter, InfoKind.Text, InfoKind.Name); }
        public String Get(StreamKind StreamKind, int StreamNumber, int Parameter) { return Get(StreamKind, StreamNumber, Parameter, InfoKind.Text); }
        public String Option(String Option_) { return Option(Option_, ""); }
        public int Count_Get(StreamKind StreamKind) { return Count_Get(StreamKind, -1); }
    }

} //NameSpace

用法 ：

using System;
using MediaInfoLib;


namespace ConsoleApplication1
{

    class Program
    {

        private static void Main(string[] args)
        {

            MediaInfo info = new MediaInfo();
            info.Open(@"E:\Songs Collection\Video's\Hindi Song's\Ajab.Si.By.HFZ.avi");
            var movie_lenstr = info.Get(StreamKind.General, 0, "Duration");
            Int32 movie_len;
            if (Int32.TryParse(movie_lenstr, out movie_len))
            {
                Console.WriteLine("Length of movie in milli-second : {0}", movie_len);
            }
            info.Close();

        }

    }

}

有很多可用的参数，所以请浏览一下文档

• 对于 x86 操作系统：这里
• 对于 x64 操作系统：这里

注意：

1. 放置mediainfo.dll在应用程序目录/系统目录中
2. 确保为 x64/x86 操作系统使用正确的 dll 构建格式，否则可能会导致

试图加载格式不正确的程序