需要帮助从c中的union转换为c＃[duplicate]

Possible Duplicate:
C++ union in C#

可能重复:C#中的C ++联合

Code in C:

C中的代码:

typedef struct _EVENT_HEADER {
USHORT              Size;                   // Event Size
USHORT              HeaderType;             // Header Type
USHORT              Flags;                  // Flags
USHORT              EventProperty;          // User given event property
ULONG               ThreadId;               // Thread Id
ULONG               ProcessId;              // Process Id
LARGE_INTEGER       TimeStamp;              // Event Timestamp
GUID                ProviderId;             // Provider Id
EVENT_DESCRIPTOR    EventDescriptor;        // Event Descriptor
union {
    struct {
        ULONG       KernelTime;             // Kernel Mode CPU ticks
        ULONG       UserTime;               // User mode CPU ticks
    } DUMMYSTRUCTNAME;
    ULONG64         ProcessorTime;          // Processor Clock 
                                            // for private session events
} DUMMYUNIONNAME;
GUID                ActivityId;             // Activity Id

} EVENT_HEADER, *PEVENT_HEADER;

I converted anything but the union. How to convert it to C#?

除了工会,我改变了任何东西。如何将其转换为C#?

2 个解决方案

#1

C# doesn't natively support the C/C++ notion of unions. You can however use the StructLayout(LayoutKind.Explicit) and FieldOffset attributes to create equivalent functionality.

C#本身并不支持C / C ++的联合概念。但是,您可以使用StructLayout(LayoutKind.Explicit)和FieldOffset属性来创建等效功能。

Regarding to union: in the code below you can see that Kernel and ProcessorTime have the same offset. LargeInteger is also a good example of union implementation in C#.

关于union:在下面的代码中,您可以看到Kernel和ProcessorTime具有相同的偏移量。 LargeInteger也是C#中联合实现的一个很好的例子。

EventHeader

[StructLayout(LayoutKind.Explicit)]
public struct EventHeader
{
    [FieldOffset(0)]
    public ushort Size;

    [FieldOffset(2)]
    public ushort HeaderType;

    [FieldOffset(4)]
    public ushort Flags;

    [FieldOffset(6)]
    public ushort EventProperty;

    [FieldOffset(8)]
    public uint ThreadId;

    [FieldOffset(12)]
    public uint ProcessId;

    [FieldOffset(16)]
    public LargeInteger TimeStamp;

    [FieldOffset(24)]
    public Guid ProviderId;

    [FieldOffset(40)]
    public Guid EventDescriptor;

    [FieldOffset(52)]
    public uint KernelTime;

    [FieldOffset(56)]
    public uint UserTime;

    [FieldOffset(52)]
    public ulong ProcessorTime;

    [FieldOffset(60)]
    public Guid ActivityId;
}

LargeInteger

[StructLayout(LayoutKind.Explicit, Size = 8)]
public struct LargeInteger
{
    [FieldOffset(0)]
    public long QuadPart;

    [FieldOffset(0)]
    public uint LowPart;

    [FieldOffset(4)]
    public uint HighPart;
}

EventDescriptor

[StructLayout(LayoutKind.Sequential)]
public struct EventDescriptor
{
    public ushort Id;

    public byte Level;

    public byte Channel;

    public byte LevelSeverity;

    public byte Opcode;

    public ushort Task;

    public uint Keyword;
}

Disclaimer: I just made this code. Didn't test it. The code may have errors.

免责声明:我刚刚制作了这段代码。没试过。代码可能有错误。

#2

You can use [StructLayout(LayoutKind.Explicit)] to explicitly place the members at the correct offsets.

您可以使用[StructLayout(LayoutKind.Explicit)]将成员显式放置在正确的偏移处。

Here is an example from an answer I provided previously

这是我之前提供的答案的一个例子

[StructLayout(LayoutKind.Explicit)]
public struct CharUnion
{
  [FieldOffset(0)] public char UnicodeChar;
  [FieldOffset(0)] public byte AsciiChar;
}

[StructLayout(LayoutKind.Explicit)]
public struct CharInfo
{
  [FieldOffset(0)] public CharUnion Char;
  [FieldOffset(2)] public short Attributes;
}

#1