我在我的WPF应用程序中调用SetWindowPlacement来保存和恢复窗口位置。这很好用，但是当窗口是工具窗口而不是标准窗口时，确保窗口永远不会完全隐藏的广告容量似乎不起作用。您使用负向左和右放置调用SetWindowPlacement，它将很乐意在屏幕外打开它，无法重新开启。
有没有办法让SetWindowPlacement更正这些工具窗口的位置（对于缺少的监视器等）？
如果做不到，有没有一个好的手工方式呢？供参考，代码：
// RECT structure required by WINDOWPLACEMENT structure
[Serializable]
[StructLayout(LayoutKind.Sequential)]
public struct RECT
{
public int Left;
public int Top;
public int Right;
public int Bottom;
public RECT(int left, int top, int right, int bottom)
{
this.Left = left;
this.Top = top;
this.Right = right;
this.Bottom = bottom;
}
}
// POINT structure required by WINDOWPLACEMENT structure
[Serializable]
[StructLayout(LayoutKind.Sequential)]
public struct POINT
{
public int X;
public int Y;
public POINT(int x, int y)
{
this.X = x;
this.Y = y;
}
}
// WINDOWPLACEMENT stores the position, size, and state of a window
[Serializable]
[StructLayout(LayoutKind.Sequential)]
public struct WINDOWPLACEMENT
{
public int length;
public int flags;
public int showCmd;
public POINT minPosition;
public POINT maxPosition;
public RECT normalPosition;
}
public static class WindowPlacement
{
private static Encoding encoding = new UTF8Encoding();
private static XmlSerializer serializer = new XmlSerializer(typeof(WINDOWPLACEMENT));
[DllImport("user32.dll")]
private static extern bool SetWindowPlacement(IntPtr hWnd, [In] ref WINDOWPLACEMENT lpwndpl);
[DllImport("user32.dll")]
private static extern bool GetWindowPlacement(IntPtr hWnd, out WINDOWPLACEMENT lpwndpl);
private const int SW_SHOWNORMAL = 1;
private const int SW_SHOWMINIMIZED = 2;
public static void SetPlacement(IntPtr windowHandle, string placementXml)
{
if (string.IsNullOrEmpty(placementXml))
{
return;
}
WINDOWPLACEMENT placement;
byte[] xmlBytes = encoding.GetBytes(placementXml);
try
{
using (MemoryStream memoryStream = new MemoryStream(xmlBytes))
{
placement = (WINDOWPLACEMENT)serializer.Deserialize(memoryStream);
}
placement.length = Marshal.SizeOf(typeof(WINDOWPLACEMENT));
placement.flags = 0;
placement.showCmd = (placement.showCmd == SW_SHOWMINIMIZED ? SW_SHOWNORMAL : placement.showCmd);
SetWindowPlacement(windowHandle, ref placement);
}
catch (InvalidOperationException)
{
// Parsing placement XML failed. Fail silently.
}
}
public static string GetPlacement(IntPtr windowHandle)
{
WINDOWPLACEMENT placement = new WINDOWPLACEMENT();
GetWindowPlacement(windowHandle, out placement);
using (MemoryStream memoryStream = new MemoryStream())
{
using (XmlTextWriter xmlTextWriter = new XmlTextWriter(memoryStream, Encoding.UTF8))
{
serializer.Serialize(xmlTextWriter, placement);
byte[] xmlBytes = memoryStream.ToArray();
return encoding.GetString(xmlBytes);
}
}
}
}
使用Top：200，Bottom：600，Left：-1000，Right：-300调用SetPlacement。
答案 0 :(得分：6)
根据Jonathan的回答，我想出了这个代码来手动救出窗口：
[StructLayout(LayoutKind.Sequential)]
public struct MONITORINFO
{
public int cbSize;
public RECT rcMonitor;
public RECT rcWork;
public uint dwFlags;
}
...
[DllImport("user32.dll")]
private static extern IntPtr MonitorFromRect([In] ref RECT lprc, uint dwFlags);
[DllImport("user32.dll")]
private static extern bool GetMonitorInfo(IntPtr hMonitor, ref MONITORINFO lpmi);
private const uint MONITOR_DEFAULTTONEAREST = 0x00000002;
...
IntPtr closestMonitorPtr = MonitorFromRect(ref placement.normalPosition, MONITOR_DEFAULTTONEAREST);
MONITORINFO closestMonitorInfo = new MONITORINFO();
closestMonitorInfo.cbSize = Marshal.SizeOf(typeof (MONITORINFO));
bool getInfoSucceeded = GetMonitorInfo(closestMonitorPtr, ref closestMonitorInfo);
if (getInfoSucceeded && !RectanglesIntersect(placement.normalPosition, closestMonitorInfo.rcMonitor))
{
placement.normalPosition = PlaceOnScreen(closestMonitorInfo.rcMonitor, placement.normalPosition);
}
...
private static bool RectanglesIntersect(RECT a, RECT b)
{
if (a.Left > b.Right || a.Right < b.Left)
{
return false;
}
if (a.Top > b.Bottom || a.Bottom < b.Top)
{
return false;
}
return true;
}
private static RECT PlaceOnScreen(RECT monitorRect, RECT windowRect)
{
int monitorWidth = monitorRect.Right - monitorRect.Left;
int monitorHeight = monitorRect.Bottom - monitorRect.Top;
if (windowRect.Right < monitorRect.Left)
{
// Off left side
int width = windowRect.Right - windowRect.Left;
if (width > monitorWidth)
{
width = monitorWidth;
}
windowRect.Left = monitorRect.Left;
windowRect.Right = windowRect.Left + width;
}
else if (windowRect.Left > monitorRect.Right)
{
// Off right side
int width = windowRect.Right - windowRect.Left;
if (width > monitorWidth)
{
width = monitorWidth;
}
windowRect.Right = monitorRect.Right;
windowRect.Left = windowRect.Right - width;
}
if (windowRect.Bottom < monitorRect.Top)
{
// Off top
int height = windowRect.Bottom - windowRect.Top;
if (height > monitorHeight)
{
height = monitorHeight;
}
windowRect.Top = monitorRect.Top;
windowRect.Bottom = windowRect.Top + height;
}
else if (windowRect.Top > monitorRect.Bottom)
{
// Off bottom
int height = windowRect.Bottom - windowRect.Top;
if (height > monitorHeight)
{
height = monitorHeight;
}
windowRect.Bottom = monitorRect.Bottom;
windowRect.Top = windowRect.Bottom - height;
}
return windowRect;
}
答案 1 :(得分：2)
您可以使用MonitorFromRect()标记将建议的窗口矩形传递给MONITOR_DEFAULTTONEAREST。这将返回一个HMONITOR，表示窗口最相交（打开）的监视器 - 或者如果窗口完全在屏幕外，则是最近的建议坐标显示器。
然后，您可以调用GetMonitorInfo()查找显示器的显示和工作区矩形，然后检查您建议的窗口坐标以确保窗口完全在屏幕上显示之前。
答案 2 :(得分：0)
我能够提出一个解决方案（基于RandomEngy的代码），该解决方案使用KeepInsideNearestMonitor（）方法扩展了Window类，以确保WPF Window放置在当前可见范围内。它没有Win32，并且可以通过右键单击“桌面”>“显示设置”在Windows 10中设置调用因子。
public static class WindowExtension
{
[StructLayout(LayoutKind.Sequential)]
internal struct RECT
{
public int Left;
public int Top;
public int Right;
public int Bottom;
public RECT(int left, int top, int right, int bottom)
{
this.Left = left;
this.Top = top;
this.Right = right;
this.Bottom = bottom;
}
}
internal static void KeepInsideNearestMonitor(this Window floatingWindow)
{
RECT normalPosition = new RECT();
normalPosition.Left = (int)floatingWindow.FloatingLeft;
normalPosition.Top = (int)floatingWindow.FloatingTop;
normalPosition.Bottom = normalPosition.Top + (int)floatingWindow.FloatingHeight;
normalPosition.Right = normalPosition.Left + (int)floatingWindow.FloatingWidth;
// Are we using only one monitor?
if (SystemParameters.PrimaryScreenWidth == SystemParameters.VirtualScreenWidth &&
SystemParameters.PrimaryScreenHeight == SystemParameters.VirtualScreenHeight)
{
RECT primaryscreen = new RECT(0,0, (int)SystemParameters.PrimaryScreenWidth, (int)SystemParameters.PrimaryScreenHeight);
if (!RectanglesIntersect(normalPosition, primaryscreen))
{
normalPosition = PlaceOnScreen(primaryscreen, normalPosition);
floatingWindow.FloatingLeft = normalPosition.Left;
floatingWindow.FloatingTop = normalPosition.Top;
floatingWindow.FloatingHeight = normalPosition.Bottom - normalPosition.Top;
floatingWindow.FloatingWidth = normalPosition.Right - normalPosition.Left;
}
return;
}
else
{
RECT primaryscreen = new RECT(0, 0, (int)SystemParameters.VirtualScreenWidth, (int)SystemParameters.VirtualScreenHeight);
if (!RectanglesIntersect(normalPosition, primaryscreen))
{
normalPosition = PlaceOnScreen(primaryscreen, normalPosition);
floatingWindow.FloatingLeft = normalPosition.Left;
floatingWindow.FloatingTop = normalPosition.Top;
floatingWindow.FloatingHeight = normalPosition.Bottom - normalPosition.Top;
floatingWindow.FloatingWidth = normalPosition.Right - normalPosition.Left;
}
return;
}
}
/// <summary>
/// Determine whether <paramref name="a"/> and <paramref name="b"/>
/// have an intersection or not.
/// </summary>
/// <param name="a"></param>
/// <param name="b"></param>
/// <returns></returns>
private static bool RectanglesIntersect(RECT a, RECT b)
{
if (a.Left > b.Right || a.Right < b.Left)
{
return false;
}
if (a.Top > b.Bottom || a.Bottom < b.Top)
{
return false;
}
return true;
}
/// <summary>
/// Determine the place where <paramref name="windowRect"/> should be placed
/// inside the <paramref name="monitorRect"/>.
/// </summary>
/// <param name="monitorRect"></param>
/// <param name="windowRect"></param>
/// <returns></returns>
private static RECT PlaceOnScreen(RECT monitorRect, RECT windowRect)
{
int monitorWidth = monitorRect.Right - monitorRect.Left;
int monitorHeight = monitorRect.Bottom - monitorRect.Top;
if (windowRect.Right < monitorRect.Left)
{
// Off left side
int width = windowRect.Right - windowRect.Left;
if (width > monitorWidth)
{
width = monitorWidth;
}
windowRect.Left = monitorRect.Left;
windowRect.Right = windowRect.Left + width;
}
else if (windowRect.Left > monitorRect.Right)
{
// Off right side
int width = windowRect.Right - windowRect.Left;
if (width > monitorWidth)
{
width = monitorWidth;
}
windowRect.Right = monitorRect.Right;
windowRect.Left = windowRect.Right - width;
}
if (windowRect.Bottom < monitorRect.Top)
{
// Off top
int height = windowRect.Bottom - windowRect.Top;
if (height > monitorHeight)
{
height = monitorHeight;
}
windowRect.Top = monitorRect.Top;
windowRect.Bottom = windowRect.Top + height;
}
else if (windowRect.Top > monitorRect.Bottom)
{
// Off bottom
int height = windowRect.Bottom - windowRect.Top;
if (height > monitorHeight)
{
height = monitorHeight;
}
windowRect.Bottom = monitorRect.Bottom;
windowRect.Top = windowRect.Bottom - height;
}
return windowRect;
}
}