WinForm程式可以透過覆寫Window.WndProc去接收視窗訊息，而在WPF程式中的處理方法跟WinForm程式有些出入，首先必須要繫上SourceInitialized事件。 public MainWindow() { InitializeComponent(); this.SourceInitialized += new EventHandler(MainWindow_SourceInitialized); }

在被繫上SourceInitialized事件的事件處理常式中將WndProc函式繫上。

void MainWindow_SourceInitialized(object sender, EventArgs e) { IntPtr hwnd = new WindowInteropHelper(this).Handle; HwndSource.FromHwnd(hwnd).AddHook(new HwndSourceHook(WndProc)); }

在WndProc函式我們就可以收到視窗訊息並做些自己想要的處理。

IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled) { switch (msg) { … } return IntPtr.Zero; }

完整的範例程式如下：

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

namespace WpfApplication2 { /// /// Interaction logic for MainWindow.xaml /// public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); this.SourceInitialized += new EventHandler(MainWindow_SourceInitialized); }

void MainWindow_SourceInitialized(object sender, EventArgs e) { IntPtr hwnd = new WindowInteropHelper(this).Handle; HwndSource.FromHwnd(hwnd).AddHook(new HwndSourceHook(WndProc)); }

IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled) { switch (msg) { //… } return IntPtr.Zero; } } }

Attaching to WndProc in WPF