问 C#为MarshalAs属性类定义自定义UnmanagedType

EN

是否可以为MarshalAs属性类定义自定义UnmanagedType？具体来说，我想将一个长的into时间转换为DateTime类型。就像这样：

[MarshalAs(UnmanagedType.LongTimeUnix)]
public DateTime Time;

我必须将自定义的LongTimeUnix枚举类型放在哪里，以及将时间转换代码放在哪里：

public static DateTime ConvertUnix2DateTime(long timeStamp)
        DateTime DT = new DateTime(1970, 1, 1, 0, 0, 0, 0);
        DT = DT.AddSeconds(timeStamp);
        return DT;
}

当将数据传输到

(SomeStruct)Marshal.PtrToStructure(
 IntPtr,
 typeof(SomeStruct));

我希望长时间的unix自动与上面的代码sinppet进行转换。我是否必须继承MarshalAs类并将转换写入这个类？谢谢你，尤尔根

更新 这里是自定义封送处理程序：

class MarshalTest : ICustomMarshaler
    public void CleanUpManagedData(object ManagedObj)
        throw new NotImplementedException();
    public void CleanUpNativeData(IntPtr pNativeData)
        throw new NotImplementedException();
    public int GetNativeDataSize()
        return 8;
    public IntPtr MarshalManagedToNative(object ManagedObj)
        throw new NotImplementedException();
    public object MarshalNativeToManaged(IntPtr pNativeData)
        long UnixTime = 0;
            UnixTime = Marshal.ReadInt64(pNativeData);
        catch (Exception e)
           QFXLogger.Error(e, "MarshalNativeToManaged");
        DateTime DT = new DateTime(1970, 1, 1, 0, 0, 0, 0);
        DT = DT.AddSeconds(UnixTime);
        return DT;
 }

以下是类的定义：

unsafe public struct MT5ServerAttributes
    /// <summary>
    /// Last known server time.
    /// </summary>
    [MarshalAs(UnmanagedType.CustomMarshaler, MarshalTypeRef = typeof(MarshalTest))]
    public DateTime CurrentTime;
    //[MarshalAs(UnmanagedType.U8)]
    [MarshalAs(UnmanagedType.CustomMarshaler, MarshalTypeRef = typeof(MarshalTest))]
    public DateTime TradeTime;
 }

最后，从非托管内存封送数据的代码：

try
   MT5ServerAttributes MT5SrvAttributes = (MT5ServerAttributes)Marshal.PtrToStructure(mMT5Proxy.MT5InformationProxy.ServerData,
                                                                    typeof(MT5ServerAttributes));