C# 处理无边框窗体

1、右击任务栏图标显示右键菜单

    
        [DllImport("user32.dll", EntryPoint = "GetWindowLong", CharSet = CharSet.Auto)]
        public static extern int GetWindowLong(HandleRef hWnd, int nIndex);

        [DllImport("user32.dll", EntryPoint = "SetWindowLong", CharSet = CharSet.Auto)]
        public static extern IntPtr SetWindowLong(HandleRef hWnd, int nIndex, int dwNewLong);


        private void ShowContextMenuStrip()
        {
            int WS_SYSMENU = 0x00080000; // 系统菜单
            int WS_MINIMIZEBOX = 0x20000; // 最大最小化按钮

            int windowLong = (GetWindowLong(new HandleRef(this, this.Handle), -16));
            SetWindowLong(new HandleRef(this, this.Handle), -16, windowLong | WS_SYSMENU | WS_MINIMIZEBOX);
        }

2、设定最大Bounds 为 主显示器的WorkingArea区域 防止最大化掩盖任务栏

           this.MaximizedBounds = Screen.PrimaryScreen.WorkingArea;