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Behavior版を追記しました。

2019/03/20 04:11

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スコア2573

test CHANGED Viewed

@@ -6,6 +6,16 @@
+(ベヘイビア版を追記しました。)
+---
+(コードビハインド版)
 - MainWindow.xaml
 ```XAML
@@ -157,3 +167,247 @@
 }
 ```
+---
+(Behavior版を追記)
+- MainWindow.xaml
+```XAML
+<Window x:Class="WpfApp1.MainWindow"
+        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
+        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
+        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
+        xmlns:i="http://schemas.microsoft.com/expression/2010/interactivity"
+        xmlns:ei="http://schemas.microsoft.com/expression/2010/interactions"
+        xmlns:local="clr-namespace:WpfApp1"
+        mc:Ignorable="d"
+        Title="MainWindow"
+        Height="450"
+        Width="800">
+    <i:Interaction.Behaviors>
+        <local:MaximizedWindowBehavior MaximizedBounds="200,500,1920,1080" />
+    </i:Interaction.Behaviors>
+    <Grid>
+    </Grid>
+</Window>
+```
+- MainWindow.xaml.cs
+既定のまま変更なし
+- MaximizedWindowBehavior.cs
+```C#
+using System;
+using System.ComponentModel;
+using System.Runtime.InteropServices;
+using System.Windows;
+using System.Windows.Interactivity;
+using System.Windows.Interop;
+namespace WpfApp1 {
+	class MaximizedWindowBehavior: Behavior<Window> {
+		#region MaximizedBounds Property
+		public Rect MaximizedBounds {
+			get => (Rect)this.GetValue( MaximizedBoundsProperty );
+			set => this.SetValue( MaximizedBoundsProperty, value );
+		}
+		public static readonly DependencyProperty MaximizedBoundsProperty =
+			DependencyProperty.Register( nameof( MaximizedBounds ), typeof( Rect ), typeof( MaximizedWindowBehavior ), new PropertyMetadata( Rect.Empty ) );
+		#endregion
+		public MaximizedWindowBehavior() { }
+		protected override void OnAttached() {
+			base.OnAttached();
+			this.AssociatedObject.Loaded += this.WindowLoaded;
+			this.AssociatedObject.Closing += this.WindowClosing;
+		}
+		protected override void OnDetaching() {
+			this.AssociatedObject.Loaded -= this.WindowLoaded;
+			this.AssociatedObject.Closing -= this.WindowClosing;
+			base.OnDetaching();
+		}
+		private void WindowLoaded( object sender, RoutedEventArgs e ) {
+			var hwnd = new WindowInteropHelper( this.AssociatedObject ).Handle;
+			var source = HwndSource.FromHwnd( hwnd );
+			source.AddHook( this.WndProc );
+		}
+		private void WindowClosing( object sender, CancelEventArgs e ) {
+			var hwnd = new WindowInteropHelper( this.AssociatedObject ).Handle;
+			var source = HwndSource.FromHwnd( hwnd );
+			source.RemoveHook( this.WndProc );
+		}
+		#region Win32
+		private struct POINT {
+			public int x;
+			public int y;
+		}
+#pragma warning disable CS0649
+		private struct MINMAXINFO {
+			public POINT ptReserved;
+			public POINT ptMaxSize;         // 最大化フォームのサイズ
+			public POINT ptMaxPosition;     // 最大化フォームの位置
+			public POINT ptMinTrackSize;    // フォームの最大サイズ
+			public POINT ptMaxTrackSize;    // フォームの最小サイズ
+		}
+#pragma warning restore CS0649
+		private const int WM_GETMINMAXINFO = 0x0024;
+		#endregion
+		private IntPtr WndProc( IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled ) {
+			if( msg == WM_GETMINMAXINFO ) {
+				handled = true;
+				var info = Marshal.PtrToStructure<MINMAXINFO>( lParam );
+				info.ptMaxPosition.x = (int)this.MaximizedBounds.Left;
+				info.ptMaxPosition.y = (int)this.MaximizedBounds.Top;
+				if( 0 < this.MaximizedBounds.Width )
+					info.ptMaxSize.x = (int)this.MaximizedBounds.Width;
+				if( 0 < this.MaximizedBounds.Height )
+					info.ptMaxSize.y = (int)this.MaximizedBounds.Height;
+				Marshal.StructureToPtr( info, lParam, true );
+				return IntPtr.Zero;
+			}
+			return IntPtr.Zero;
+		}
+	}
+}
+```