如何使用低级别的8位标志，如条件？ [英] How do I use low-level 8 bit flags as conditionals?

问题描述

在我的键盘钩子，每个按键得到指出，如果它被注入与否的标志。
http://msdn.microsoft.com/en-us/library /ms644967(VS.85).aspx

In my keyboard hook, each keypress gets a flag that states if it was injected or not. http://msdn.microsoft.com/en-us/library/ms644967(VS.85).aspx

我蒸馏脱除lParam的一个KBDLLHOOKSTRUCT。我可以访问kbd.flags.XXX。我只是不知道如何将这种8bit的标志转换成如果（注射）{... 键入条件，我知道如何使用。

I've distilled a KBDLLHOOKSTRUCT from the lParam. I can access kbd.flags.XXX. I just don't know how to convert this 8bit flag into an if (injected) {... type conditional that I know how to use.

如果你聪明的计算机科学类型的人会帮助我我会很感激。

If one of you smart computer-science types would help me out I'd really appreciate it.

    private static IntPtr HookCallback(int nCode, IntPtr wParam, IntPtr lParam)
    {
        KBDLLHOOKSTRUCT kbd = new KBDLLHOOKSTRUCT();
        Marshal.PtrToStructure(lParam, kbd);

        //if (injected) {...

干杯！

Cheers!

推荐答案

您需要按位与它带着面具。例如，注入的位位4这是二进制00010000，十六进制为0x10。所以，你按位与它为0x10，并查看是否有左：

You need to bitwise-and it with a mask. For example, the injected bit is bit 4. That's binary 00010000, hex 0x10. So you bitwise-and it with 0x10, and see if anything's left:

bool isInjected = ((kbd.flags & 0x10) != 0);

（当然，按照安德鲁的答案，这将是一个好主意，定义一个LLKHF_INJECTED常数这个而不是直接包括代码的十六进制值！）

(Of course, as per Andrew's answer, it would be a good idea to define a LLKHF_INJECTED constant for this rather than including the hex value directly in your code!)

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