你需要找到点Left、Top、Height、Width并直接设置到你想要最大化的窗口
MonitorFromPoint
MonitorFromRect
MonitorFromWindow
为了完整起见，我首先介绍如何在指定监视器上最大化窗口的简单方法。
void Maximize(HWND hWnd, HMONITOR hMonitor)
{
// access monitor info
MONITORINFO monitorInfo = { sizeof(MONITORINFO) };
GetMonitorInfo(hMonitor, &monitorInfo);
// restore window to normal size if it is not yet
ShowWindow(hWnd, SW_RESTORE);
// move window to the monitor
SetWindowPos(hWnd, nullptr, monitorInfo.rcMonitor.left,
monitorInfo.rcMonitor.top, 0, 0, SWP_NOZORDER | SWP_NOSIZE);
// maximize window
ShowWindow(hWnd, SW_MAXIMIZE);
}
如果函数在相同的输入窗口和相同的目标监视器下多次调用，闪烁会更加明显。当然，有人可能会争辩说，可以获取窗口的当前状态并避免调用函数（或者如果检测到状态已经正确，则在函数中提前返回）。然而，这样的处理只会增加函数的复杂性。我在想是否不可能只是隐藏窗口并在后台以某种方式执行状态恢复，并且只在最后显示窗口。但是尝试注入一些 SetRender(hWnd, FALSE) 或 ShowWindow(SW_HIDE) 调用只会使输出变得更糟。经过一些测试，我发现更改最大化/正常窗口只会更改窗口样式中的一点（WS_MAXIMIZE），最后有了这些信息，我得到了最终的好解决方案：
void Maximize(HWND hWnd, HMONITOR hMonitor)
{
// access monitor info
MONITORINFO monitorInfo = { sizeof(MONITORINFO) };
GetMonitorInfo(hMonitor, &monitorInfo);
const LONG currStyles = GetWindowLong(hWnd, GWL_STYLE);
SetWindowLong(hWnd, GWL_STYLE, currStyles | WS_MAXIMIZE);
const auto rc = monitorInfo.rcMonitor;
SetWindowPos(&CWnd::wndTop, rc.left, rc.top, rc.Width(), rc.Height(), 0);
}
就是这样。该函数按预期工作，即使多次调用，也没有闪烁。通过从窗口样式中删除 WS_MAXIMIZE 并使用正确的矩形信息调用 SetWindowPos，可以轻松更改该函数以将窗口恢复为正常大小。
[DllImport("User32.dll")]
private static extern IntPtr MonitorFromPoint([In]System.Drawing.Point pt, [In]uint dwFlags);
//https://msdn.microsoft.com/en-us/library/windows/desktop/dn280510(v=vs.85).aspx
[DllImport("Shcore.dll")]
private static extern IntPtr GetDpiForMonitor([In]IntPtr hmonitor, [In]DpiType dpiType, [Out]out uint dpiX, [Out]out uint dpiY);
public enum DpiType
{
Effective = 0,
Angular = 1,
Raw = 2,
}
/// <summary>
/// POINT aka POINTAPI
/// </summary>
[StructLayout(LayoutKind.Sequential)]
public struct POINT
{
/// <summary>
/// x coordinate of point.
/// </summary>
public int x;
/// <summary>
/// y coordinate of point.
/// </summary>
public int y;
/// <summary>
/// Construct a point of coordinates (x,y).
/// </summary>
public POINT(int x, int y)
{
this.x = x;
this.y = y;
}
}
[StructLayout(LayoutKind.Sequential)]
public struct MINMAXINFO
{
public POINT ptReserved;
public POINT ptMaxSize;
public POINT ptMaxPosition;
public POINT ptMinTrackSize;
public POINT ptMaxTrackSize;
};
/// <summary>
/// </summary>
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
public class MONITORINFO
{
/// <summary>
/// </summary>
public int cbSize = Marshal.SizeOf(typeof(MONITORINFO));
/// <summary>
/// </summary>
public RECT rcMonitor = new RECT();
/// <summary>
/// </summary>
public RECT rcWork = new RECT();
/// <summary>
/// </summary>
public int dwFlags = 0;
}
/// <summary> Win32 </summary>
[StructLayout(LayoutKind.Sequential, Pack = 0)]
public struct RECT
{
/// <summary> Win32 </summary>
public int left;
/// <summary> Win32 </summary>
public int top;
/// <summary> Win32 </summary>
public int right;
/// <summary> Win32 </summary>
public int bottom;
/// <summary> Win32 </summary>
public static readonly RECT Empty = new RECT();
/// <summary> Win32 </summary>
public int Width
{
get { return Math.Abs(right - left); } // Abs needed for BIDI OS
}
/// <summary> Win32 </summary>
public int Height
{
get { return bottom - top; }
}
/// <summary> Win32 </summary>
public RECT(int left, int top, int right, int bottom)
{
this.left = left;
this.top = top;
this.right = right;
this.bottom = bottom;
}
/// <summary> Win32 </summary>
public RECT(RECT rcSrc)
{
this.left = rcSrc.left;
this.top = rcSrc.top;
this.right = rcSrc.right;
this.bottom = rcSrc.bottom;
}
/// <summary> Win32 </summary>
public bool IsEmpty
{
get
{
// BUGBUG : On Bidi OS (hebrew arabic) left > right
return left >= right || top >= bottom;
}
}
/// <summary> Return a user friendly representation of this struct </summary>
public override string ToString()
{
if (this == RECT.Empty) { return "RECT {Empty}"; }
return "RECT { left : " + left + " / top : " + top + " / right : " + right + " / bottom : " + bottom + " }";
}
/// <summary> Determine if 2 RECT are equal (deep compare) </summary>
public override bool Equals(object obj)
{
if (!(obj is Rect)) { return false; }
return (this == (RECT)obj);
}
/// <summary>Return the HashCode for this struct (not garanteed to be unique)</summary>
public override int GetHashCode()
{
return left.GetHashCode() + top.GetHashCode() + right.GetHashCode() + bottom.GetHashCode();
}
/// <summary> Determine if 2 RECT are equal (deep compare)</summary>
public static bool operator ==(RECT rect1, RECT rect2)
{
return (rect1.left == rect2.left && rect1.top == rect2.top && rect1.right == rect2.right && rect1.bottom == rect2.bottom);
}
/// <summary> Determine if 2 RECT are different(deep compare)</summary>
public static bool operator !=(RECT rect1, RECT rect2)
{
return !(rect1 == rect2);
}
}
[DllImport("user32")]
internal static extern bool GetMonitorInfo(IntPtr hMonitor, MONITORINFO lpmi);
[DllImport("User32")]
internal static extern IntPtr MonitorFromWindow(IntPtr handle, int flags);
链接：-
http://msdn.microsoft.com/en-us/library/windows/desktop/dd145071%28v=vs.85%29.aspx
http://blogs.msdn.com/b/oldnewthing/archive/2010/04/12/9994016.aspx