WPF 不同DPI下，窗口大小的处理

 1 <Window x:Class="WindowHeightChangedForDpi.MainWindow"
 2         xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
 3         xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
 4         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
 5         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
 6         xmlns:local="clr-namespace:WindowHeightChangedForDpi"
 7         mc:Ignorable="d"
 8         Title="MainWindow" SizeToContent="WidthAndHeight" WindowStartupLocation="CenterScreen">
 9     <Viewbox x:Name="RootViewbox" Stretch="None">
10         <Grid x:Name="RootGrid" Width="1000" MaxHeight="680" MinHeight="520" ClipToBounds="True">
11 
12         </Grid>
13     </Viewbox>
14 </Window>

 1     public partial class MainWindow : Window
 2     {
 3         public MainWindow()
 4         {
 5             InitializeComponent();
 6             Loaded += InitWindowActualHeight_OnLoaded;
 7         }
 8 
 9         #region 设置窗口对屏幕高度的自适应
10 
11         private void InitWindowActualHeight_OnLoaded(object sender, RoutedEventArgs e)
12         {
13             Loaded -= InitWindowActualHeight_OnLoaded;
14             InitWindowActualHeight();
15         }
16 
17         private const double WindowShadowHeight = 0;
18 
19         private void InitWindowActualHeight()
20         {
21             //获取任务栏高度
22             var taskbarHeight = SystemParameters.PrimaryScreenHeight - SystemParameters.WorkArea.Height;
23             //获取窗体所在屏幕的高度
24             var height = GetScreenHeight();
25             var visibleAreaHeight = height - taskbarHeight;
26 
27             //可显示高度 > 窗口最大高度
28             if (visibleAreaHeight > RootGrid.MaxHeight + WindowShadowHeight)
29             {
30                 //设置高度等于最大高度
31                 RootGrid.Height = RootGrid.MaxHeight;
32             }
33             //可显示高度 < 窗口最小高度
34             else if (visibleAreaHeight < RootGrid.MinHeight + WindowShadowHeight)
35             {
36                 //设置Viewbox高度=可视高度-阴影高度（此处通过绽放显示窗口，所以不能通过设置窗口或者设置内容的高度来实现）
37                 RootViewbox.Height = visibleAreaHeight - WindowShadowHeight;
38                 //等比例缩小
39                 RootViewbox.Stretch = Stretch.Uniform;
40             }
41             else
42             {
43                 //设置高度等于最小高度
44                 RootGrid.Height = RootGrid.MinHeight;
45             }
46         }
47         const double DpiPercent = 96;
48         private double GetScreenHeight()
49         {
50             var intPtr = new WindowInteropHelper(this).Handle;//获取当前窗口的句柄
51             var screen = Screen.FromHandle(intPtr);//获取当前屏幕
52 
53             double height = 0;
54             using (Graphics currentGraphics = Graphics.FromHwnd(intPtr))
55             {
56                 double dpiXRatio = currentGraphics.DpiX / DpiPercent;
57                 double dpiYRatio = currentGraphics.DpiY / DpiPercent;
58                 height = screen.Bounds.Height / dpiYRatio;
59                 //var width = screen.Bounds.Width / dpiXRatio;
60                 //var left = screen.Bounds.Left / dpiXRatio;
61                 //var top = screen.Bounds.Top / dpiYRatio;
62             }
63             return height;
64         }
65         #endregion