1

下面是一个完整的程序。只要您不取消注释顶部的“#define BROKEN”，它就可以正常工作。中断是由于 PInvoke 未能正确编组联合。有问题的INPUT_RECORD结构有许多子结构，可能会根据 EventType 中的值使用。

我不明白的是，当我只定义它的单个子结构时，KEY_EVENT_RECORD它与偏移量 4 处的显式声明一起工作。但是当我在相同的偏移量处添加其他结构时，结构的内容完全被淹没了。

//UNCOMMENT THIS LINE TO BREAK IT:
//#define BROKEN

using System;
using System.Runtime.InteropServices;

class ConIOBroken
{
    static void Main()
    {
        int nRead = 0;
        IntPtr handle = GetStdHandle(-10 /*STD_INPUT_HANDLE*/);
        Console.Write("Press the letter: 'a': ");

        INPUT_RECORD record = new INPUT_RECORD();
        do
        {
            ReadConsoleInputW(handle, ref record, 1, ref nRead);
        } while (record.EventType != 0x0001/*KEY_EVENT*/);

        Assert.AreEqual((short)0x0001, record.EventType);
        Assert.AreEqual(true, record.KeyEvent.bKeyDown);
        Assert.AreEqual(0x00000000, record.KeyEvent.dwControlKeyState & ~0x00000020);//strip num-lock and test
        Assert.AreEqual('a', record.KeyEvent.UnicodeChar);
        Assert.AreEqual((short)0x0001, record.KeyEvent.wRepeatCount);
        Assert.AreEqual((short)0x0041, record.KeyEvent.wVirtualKeyCode);
        Assert.AreEqual((short)0x001e, record.KeyEvent.wVirtualScanCode);
    }

    static class Assert { public static void AreEqual(object x, object y) { if (!x.Equals(y)) throw new ApplicationException(); } }

    [DllImport("Kernel32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
    public static extern IntPtr GetStdHandle(int nStdHandle);

    [DllImport("Kernel32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
    public static extern bool ReadConsoleInputW(IntPtr hConsoleInput, ref INPUT_RECORD lpBuffer, int nLength, ref int lpNumberOfEventsRead);

    [StructLayout(LayoutKind.Explicit)]
    public struct INPUT_RECORD
    {
        [FieldOffset(0)]
        public short EventType;
        //union {
        [FieldOffset(4)]
        public KEY_EVENT_RECORD KeyEvent;
#if BROKEN
        [FieldOffset(4)]
        public MOUSE_EVENT_RECORD MouseEvent;
        [FieldOffset(4)]
        public WINDOW_BUFFER_SIZE_RECORD WindowBufferSizeEvent;
        [FieldOffset(4)]
        public MENU_EVENT_RECORD MenuEvent;
        [FieldOffset(4)]
        public FOCUS_EVENT_RECORD FocusEvent;
        //}
#endif
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct KEY_EVENT_RECORD
    {
        public bool bKeyDown;
        public short wRepeatCount;
        public short wVirtualKeyCode;
        public short wVirtualScanCode;
        public char UnicodeChar;
        public int dwControlKeyState;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct MOUSE_EVENT_RECORD
    {
        public COORD dwMousePosition;
        public int dwButtonState;
        public int dwControlKeyState;
        public int dwEventFlags;
    };

    [StructLayout(LayoutKind.Sequential)]
    public struct WINDOW_BUFFER_SIZE_RECORD
    {
        public COORD dwSize;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct MENU_EVENT_RECORD
    {
        public int dwCommandId;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct FOCUS_EVENT_RECORD
    {
        public bool bSetFocus;
    }

    [StructLayout(LayoutKind.Sequential)]
    public struct COORD
    {
        public short X;
        public short Y;
    }
}

更新：

对于那些担心结构声明本身的人：

  1. bool 被视为 32 位值
  2. 数据上使用 offset(4) 的原因是允许 32 位结构对齐，这可以防止联合从偏移量 2 开始。

同样，我的问题根本不是使 PInvoke 工作，它试图弄清楚为什么这些额外的结构（假设在相同的偏移量）通过简单地添加它们来收集数据。

4

6 回答 6

2

我相信如果你制作 uint 类型的 bSetFocus 和 dwCommandId 它将起作用。

将来，请查看PInvoke wiki以获取正确的签名。它通常是准确的，或者至少是一个很好的起点。

于 2009-10-21T18:17:55.973 回答
1

1) public bool bKeyDown 应该是 Int32 bKeyDown 因为它是 C++ 中的 BOOL (4bytes)

2) public bool bSetFocus 应该是 Int32

于 2009-10-21T18:21:17.720 回答
1 


//UNCOMMENT THIS LINE TO BREAK IT:
//#define BROKEN



using System;
using System.Runtime.InteropServices;



class ConIOBroken
{
    static void Main()
    {
        int nRead = 0;
        IntPtr handle = GetStdHandle(-10 /STD_INPUT_HANDLE/);
        Console.Write("Press the letter: 'a': ");



    INPUT_RECORD record = new INPUT_RECORD();
    do
    {
        ReadConsoleInputW(handle, ref record, 1, ref nRead);
    } while (record.EventType != 0x0001/*KEY_EVENT*/);

    Assert.AreEqual((short)0x0001, record.EventType);
    Assert.AreEqual(1u, record.KeyEvent.bKeyDown);
    Assert.AreEqual(0x00000000, record.KeyEvent.dwControlKeyState & ~0x00000020);//strip num-lock and test
    Assert.AreEqual('a', record.KeyEvent.UnicodeChar);
    Assert.AreEqual((short)0x0001, record.KeyEvent.wRepeatCount);
    Assert.AreEqual((short)0x0041, record.KeyEvent.wVirtualKeyCode);
    Assert.AreEqual((short)0x001e, record.KeyEvent.wVirtualScanCode);
    return;
}

static class Assert { public static void AreEqual(object x, object y) { if (!x.Equals(y)) throw new ApplicationException(); } }

[DllImport("Kernel32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
public static extern IntPtr GetStdHandle(int nStdHandle);

[DllImport("Kernel32.dll", CharSet = CharSet.Unicode, SetLastError = true)]
public static extern bool ReadConsoleInputW(IntPtr hConsoleInput, ref INPUT_RECORD lpBuffer, int nLength, ref int lpNumberOfEventsRead);

[StructLayout(LayoutKind.Explicit)]
public struct INPUT_RECORD
{
    [FieldOffset(0)]
    public short EventType;
    //union {
    [FieldOffset(4)]
    public KEY_EVENT_RECORD KeyEvent;
    [FieldOffset(4)]
    public MOUSE_EVENT_RECORD MouseEvent;
    [FieldOffset(4)]
    public WINDOW_BUFFER_SIZE_RECORD WindowBufferSizeEvent;
    [FieldOffset(4)]
    public MENU_EVENT_RECORD MenuEvent;
    [FieldOffset(4)]
    public FOCUS_EVENT_RECORD FocusEvent;
}

[StructLayout(LayoutKind.Sequential)]
public struct KEY_EVENT_RECORD
{
    public uint bKeyDown;
    public short wRepeatCount;
    public short wVirtualKeyCode;
    public short wVirtualScanCode;
    public char UnicodeChar;
    public int dwControlKeyState;
}

[StructLayout(LayoutKind.Sequential)]
public struct MOUSE_EVENT_RECORD
{
    public COORD dwMousePosition;
    public int dwButtonState;
    public int dwControlKeyState;
    public int dwEventFlags;
};

[StructLayout(LayoutKind.Sequential)]
public struct WINDOW_BUFFER_SIZE_RECORD
{
    public COORD dwSize;
}

[StructLayout(LayoutKind.Sequential)]
public struct MENU_EVENT_RECORD
{
    public int dwCommandId;
}

[StructLayout(LayoutKind.Sequential)]
public struct FOCUS_EVENT_RECORD
{
    public uint bSetFocus;
}

[StructLayout(LayoutKind.Sequential)]
public struct COORD
{
    public short X;
    public short Y;
}




}

于 2009-10-21T18:35:07.687 回答
0

只是一个想法，如果你最后声明最大的字段会发生什么？也许 P/Invoke 正在复制到最后一个字段，该字段在早期字段之前结束。

于 2009-10-21T18:10:13.947 回答
0

尝试将手动计算的 Size 字段添加到 StructLayout 属性，如下所示：

[StructLayout(LayoutKind.Explicit, Size=...)]
于 2009-10-21T18:20:36.373 回答
0

带有 bool 的原始代码包含 13 个字节，从 FieldOffset(4) 开始......
以MOUSE_EVENT_RECORD相同偏移量开始包含从相同偏移量开始的 16 个字节。

当您将 bool (1byte) 更改为 uint(4bytes) 时，您组成了 3 个字节。

于 2010-04-02T14:52:30.343 回答