MainWindow.xaml(父窗体)
<StackPanel> <Label Content="{Binding Message}"/> <Button Content="Input User Name" Command="{Binding OpenSubWindowCommand}"/> </StackPanel>
MainWindow.xaml.cs
public MainWindow() { InitializeComponent(); this.DataContext = new MainWindowViewModel(); }
MainWindowViewModel.cs
class MainWindowViewModel : INotifyPropertyChanged { string message; public event PropertyChangedEventHandler PropertyChanged; public void OnPropertyChanged(string propertyName) { if (PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); } } public string Message { get => message; set { message = value; OnPropertyChanged("Message"); } } public ICommand OpenSubWindowCommand { get; set; } public MainWindowViewModel() { OpenSubWindowCommand = new CommandHandler(OpenSubWindow); } void OpenSubWindow() { SubWindow subWindow = new SubWindow((name) => { Message = $"hello {name}"; }); subWindow.Show(); } }
SubWindow.xaml(子窗体)
<StackPanel> <TextBox Text="{Binding Name}"/> <Button Content="Send" Command="{Binding SendCommand}"/> </StackPanel>
SubWindow.xaml.cs
public SubWindow(Action<string> callback) { InitializeComponent(); this.DataContext = new SubWindowViewModel(callback, this); }
SubWindowViewModel.cs
class SubWindowViewModel : INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged; void OnPropertyChanged(string propertyName) { if (PropertyChanged != null) PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); } string name; public string Name { get => name; set { name = value; OnPropertyChanged("Name"); } } Action<string> Callback { get; set; } SubWindow Window { get; set; } public SubWindowViewModel(Action<string> callback, SubWindow window) { SendCommand = new CommandHandler(Send); Callback = callback; Window = window; } public ICommand SendCommand { get; set; } void Send() { if (Callback != null) { Callback(name); Window.Close(); } } }