WPF设置一个透明窗体,鼠标可以透过窗体点击下面的东西

前台

<Window x:Class="hittest.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:local="clr-namespace:hittest"
mc:Ignorable="d"
Title="MainWindow" IsHitTestVisible="True" Topmost="True" AllowsTransparency="True" Background="#66FFFFFF" WindowStyle="None" WindowState="Maximized" ResizeMode="NoResize">
<Grid>

</Grid>
</Window>

后台

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Interop;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace hittest
{
/// <summary>
/// MainWindow.xaml 的交互逻辑
/// </summary>
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
}
public static class WindowsServices
{
const int WS_EX_TRANSPARENT = 0x00000020;
const int GWL_EXSTYLE = (-20);

[DllImport("user32.dll")]
static extern int GetWindowLong(IntPtr hwnd, int index);

[DllImport("user32.dll")]
static extern int SetWindowLong(IntPtr hwnd, int index, int newStyle);

public static void SetWindowExTransparent(IntPtr hwnd)
{
var extendedStyle = GetWindowLong(hwnd, GWL_EXSTYLE);
SetWindowLong(hwnd, GWL_EXSTYLE, extendedStyle | WS_EX_TRANSPARENT);
}
}
protected override void OnSourceInitialized(EventArgs e)
{
base.OnSourceInitialized(e);
var hwnd = new WindowInteropHelper(this).Handle;
WindowsServices.SetWindowExTransparent(hwnd);
}
}
}