Windows 回调，当活动窗口改变时答案

【问题标题】：Windows Callback, When The Active Window ChangedWindows 回调，当活动窗口改变时
【发布时间】：2012-03-05 12:34:28
【问题描述】：

public class ActiveWindow
{
public delegate void ActiveWindowChangedHandler(object sender, String windowHeader,IntPtr hwnd);
public event ActiveWindowChangedHandler ActiveWindowChanged;

[DllImport("user32.dll")]
static extern IntPtr GetForegroundWindow();
[DllImport("user32.dll")]
static extern int GetWindowText(IntPtr hWnd, StringBuilder text, int count);

delegate void WinEventDelegate(IntPtr hWinEventHook, uint eventType,
    IntPtr hwnd, int idObject, int idChild, uint dwEventThread,
    uint dwmsEventTime);

const uint WINEVENT_OUTOFCONTEXT = 0;
const uint EVENT_SYSTEM_FOREGROUND = 3;

[DllImport("user32.dll")]
static extern bool UnhookWinEvent(IntPtr hWinEventHook);

[DllImport("user32.dll")]
static extern IntPtr SetWinEventHook(uint eventMin, uint eventMax,
    IntPtr hmodWinEventProc, WinEventDelegate lpfnWinEventProc,
    uint idProcess, uint idThread, uint dwFlags);

IntPtr m_hhook;
private WinEventDelegate _winEventProc;

public ActiveWindow()
{
    _winEventProc = new WinEventDelegate(WinEventProc);
    m_hhook = SetWinEventHook(EVENT_SYSTEM_FOREGROUND,
        EVENT_SYSTEM_FOREGROUND, IntPtr.Zero, _winEventProc,
        0, 0, WINEVENT_OUTOFCONTEXT);
}

void WinEventProc(IntPtr hWinEventHook, uint eventType, IntPtr hwnd,
    int idObject, int idChild, uint dwEventThread, uint dwmsEventTime)
{
    if (eventType == EVENT_SYSTEM_FOREGROUND)
    {
        if (ActiveWindowChanged != null)
            ActiveWindowChanged(this,GetActiveWindowTitle(hwnd),hwnd);
    }
}

private string GetActiveWindowTitle(IntPtr hwnd)
{
    StringBuilder Buff = new StringBuilder(500);
    GetWindowText(hwnd, Buff, Buff.Capacity);
    return Buff.ToString();
}

~ActiveWindow()
{
    UnhookWinEvent(m_hhook);
}
}

当我在活动窗口之间切换时，我会收到回调但是当我最大化一个最小化的窗口时，我没有收到回电，

我找到了解决这个问题的方法，但我正在寻找更好的解决方案

我们将不胜感激。

【问题讨论】：

codeproject.com/Questions/328990/…

标签： c# .net wpf windows-7

【解决方案1】：

当我在活动窗口之间切换时，我得到回调，但是当我最大化最小化窗口时，我没有得到回调

是的，您需要使用EVENT_SYSTEM_MINIMIZESTART 或EVENT_SYSTEM_MINIMIZEEND event constant 来接收窗口对象被最小化的通知。

使用SetWinEventHook function 的eventMin 和eventMax 参数表明您有兴趣接收这些事件之一的通知和 EVENT_SYSTEM_FOREGROUND。

【讨论】：