如何使用裝飾器從各個方面實現窗口大小調整？

Question

我有一個無邊框透明的WPF窗口（WindowStyle = None），我希望能夠從各個方面調整大小。如果我設置ResizeMode = CanResizeWithGrip，目前只能使用上述設置調整大小。這對視覺提示很好，但不是很好，因爲你只能從一個角落調整大小。

我想用裝飾者來做這件事，所以當窗口處於調整大小模式（可以打開和關閉）時，我也可以給出一個視覺提示。這可能嗎？如果是這樣，我該怎麼辦呢？

Answer 1

此問題已經在stackoverflow的某處回答。我現在無法真正找到它，但這是我如何做到的。

主窗口：

<Window x:Class="Solution.Views.Main.MainWindow" 
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
    Title="MainWindow" MinWidth="1000" MinHeight="500" WindowStyle="None" AllowsTransparency="False" BorderThickness="0" ResizeMode="NoResize"> 

    <Window.TaskbarItemInfo> 
    <TaskbarItemInfo /> 
    </Window.TaskbarItemInfo> 

    <Grid> 

    <Border MouseLeftButtonDown="WindowResizeEast" MouseEnter="BorderVertical_OnMouseEnter" MouseLeave="BorderAll_OnMouseLeave" VerticalAlignment="Stretch" HorizontalAlignment="Right" Width="1" Background="Black"/> 
    <Border MouseLeftButtonDown="WindowResizeWest" MouseEnter="BorderVertical_OnMouseEnter" MouseLeave="BorderAll_OnMouseLeave" VerticalAlignment="Stretch" HorizontalAlignment="Left" Width="1" Background="Black"/> 
    <Border MouseLeftButtonDown="WindowResizeNorth" MouseEnter="BorderHorizontal_OnMouseEnter" MouseLeave="BorderAll_OnMouseLeave" VerticalAlignment="Top" HorizontalAlignment="Stretch" Height="1" Background="Black"/> 
    <Border MouseLeftButtonDown="WindowResizeSouth" MouseEnter="BorderHorizontal_OnMouseEnter" MouseLeave="BorderAll_OnMouseLeave" VerticalAlignment="Bottom" HorizontalAlignment="Stretch" Height="1" Background="Black"/> 
    <Border VerticalAlignment="Bottom" HorizontalAlignment="Right" Width="20" Height="20" MouseEnter="BorderSouthEast_OnMouseEnter" MouseLeave="BorderAll_OnMouseLeave" MouseLeftButtonDown="UIElement_OnMouseLeftButtonDown"> 
     <Grid> 
      <Path Stroke="Gray" StrokeThickness="1" Data=" M 5 20 L 20 5 M 10 20 L 20 10 M 15 20 L 20 15"/> 
     </Grid> 
    </Border> 
    </Grid> 
</Window> 

主窗口代碼：

using System; 
using System.Diagnostics; 
using System.Linq; 
using System.Runtime.InteropServices; 
using System.Windows; 
using System.Windows.Input; 
using System.Windows.Interop; 
using System.Windows.Media; 
using PrmWpf.Services; 

public partial class MainWindow 
{ 
    public MainWindow() 
    { 
     InitializeComponent(); 
    } 

    [DllImport("user32.dll", CharSet = CharSet.Auto)] 
    private static extern IntPtr SendMessage(IntPtr hWnd, uint msg, IntPtr wParam, IntPtr lParam); 

    [DllImportAttribute("user32.dll")] 
    public static extern bool ReleaseCapture(); 

    private void WindowResizeNorth(object sender, MouseButtonEventArgs e) //PreviewMousLeftButtonDown 
    { 
     var hwndSource = PresentationSource.FromVisual((Visual)sender) as HwndSource; 
     SendMessage(hwndSource.Handle, 0x112, (IntPtr)ResizeDirection.Top, IntPtr.Zero); 
    } 

    private void WindowResizeSouth(object sender, MouseButtonEventArgs e) //PreviewMousLeftButtonDown 
    { 
     var hwndSource = PresentationSource.FromVisual((Visual)sender) as HwndSource; 
     SendMessage(hwndSource.Handle, 0x112, (IntPtr)ResizeDirection.Bottom, IntPtr.Zero); 
    } 

    private void WindowResizeWest(object sender, MouseButtonEventArgs e) //PreviewMousLeftButtonDown 
    { 
     var hwndSource = PresentationSource.FromVisual((Visual)sender) as HwndSource; 
     SendMessage(hwndSource.Handle, 0x112, (IntPtr)ResizeDirection.Left, IntPtr.Zero); 
    } 

    private void WindowResizeEast(object sender, MouseButtonEventArgs e) //PreviewMousLeftButtonDown 
    { 
     var hwndSource = PresentationSource.FromVisual((Visual)sender) as HwndSource; 
     SendMessage(hwndSource.Handle, 0x112, (IntPtr)ResizeDirection.Right, IntPtr.Zero); 
    } 

    private enum ResizeDirection { Left = 61441, Right = 61442, Top = 61443, Bottom = 61446, BottomRight = 61448, } 

    private void BorderVertical_OnMouseEnter(object sender, MouseEventArgs e) 
    { 
     Mouse.OverrideCursor = Cursors.SizeWE; 
    } 

    private void BorderHorizontal_OnMouseEnter(object sender, MouseEventArgs e) 
    { 
     Mouse.OverrideCursor = Cursors.SizeNS; 
    } 

    private void BorderAll_OnMouseLeave(object sender, MouseEventArgs e) 
    { 
     Mouse.OverrideCursor = Cursors.Arrow; 
    } 

    private void BorderSouthEast_OnMouseEnter(object sender, MouseEventArgs e) 
    { 
     Mouse.OverrideCursor = Cursors.SizeNWSE; 
    } 

    private void UIElement_OnMouseLeftButtonDown(object sender, MouseButtonEventArgs e) 
    { 
     var hwndSource = PresentationSource.FromVisual((Visual)sender) as HwndSource; 
     SendMessage(hwndSource.Handle, 0x112, (IntPtr)ResizeDirection.BottomRight, IntPtr.Zero); 
    } 
}