c# - 在 2 个监视器上最大化 WPF 窗口

Question

如标题我希望我的 WPF 在 2 个显示器上最大化(现在我的电脑有 2 个显示器)。我设置

this.Width = System.Windows.Forms.Screen.AllScreens[0].Bounds.Width + System.Windows.Forms.Screen.AllScreens[1].Bounds.Width 

但它不是完整的，像图像一样有间隔。我希望用户单击最大化按钮然后窗口最大化 2 监视器。有人知道吗？谢谢大家!

p/s:抱歉我的英语不好。

Answer 1

需要找到点Left,Top,Height,Width直接设置成你想最大化的窗口

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朴素方法。

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);    
}

如果使用相同的输入窗口和相同的目标监视器多次调用函数，则闪烁会更加明显。当然，有人会争辩说，可以获取窗口的当前状态并避免调用该函数(或者如果检测到状态已经正确，则在函数中进行一些提前返回)。然而，这样的处理只会增加函数的复杂性。我在想是否有可能只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(inject)一些 SetRender(hWnd, FALSE) 或 ShowWindow(SW_HIDE) 调用只会让输出变得更糟。经过一些测试，我发现改变最大化/正常窗口只会改变窗口样式中的一位 (WS_MAXIMIZE)，最后根据这些信息我得到了最终的好的解决方案:

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，可以轻松更改此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);

Links:- 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