WPF Input and Commands Patterns

WPF Input and Commands Patterns

MVVM Framework Rule: .claude/rules/dotnet/wpf/mvvm-framework.md 설정에 따라 코드 스타일이 결정됩니다. Prism 9 사용 시 → PRISM.md 참조

Handling user input and implementing command patterns in WPF applications.

1. Command System Overview

ICommand (Interface)
├── RoutedCommand (WPF built-in)
│   ├── ApplicationCommands (Copy, Paste, Cut, etc.)
│   ├── NavigationCommands (BrowseBack, BrowseForward, etc.)
│   ├── MediaCommands (Play, Pause, Stop, etc.)
│   └── EditingCommands (ToggleBold, ToggleItalic, etc.)
└── RelayCommand / DelegateCommand (MVVM)

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2. Built-in Commands

2.1 ApplicationCommands

<Window.CommandBindings>
    <CommandBinding Command="ApplicationCommands.Copy"
                    Executed="CopyCommand_Executed"
                    CanExecute="CopyCommand_CanExecute"/>
    <CommandBinding Command="ApplicationCommands.Paste"
                    Executed="PasteCommand_Executed"/>
</Window.CommandBindings>

<StackPanel>
    <Button Command="ApplicationCommands.Copy" Content="Copy (Ctrl+C)"/>
    <Button Command="ApplicationCommands.Paste" Content="Paste (Ctrl+V)"/>
    <Button Command="ApplicationCommands.Undo" Content="Undo (Ctrl+Z)"/>
    <Button Command="ApplicationCommands.Redo" Content="Redo (Ctrl+Y)"/>
</StackPanel>

private void CopyCommand_Executed(object sender, ExecutedRoutedEventArgs e)
{
    // Copy logic
    Clipboard.SetText(SelectedText);
}

private void CopyCommand_CanExecute(object sender, CanExecuteRoutedEventArgs e)
{
    // Enable condition
    e.CanExecute = !string.IsNullOrEmpty(SelectedText);
}

2.2 Common Built-in Commands

Category	Commands
ApplicationCommands	New, Open, Save, SaveAs, Close, Print, Copy, Cut, Paste, Undo, Redo, Find, Replace, SelectAll, Delete, Properties, Help
NavigationCommands	BrowseBack, BrowseForward, BrowseHome, BrowseStop, Refresh, Favorites, Search, GoToPage, NextPage, PreviousPage, FirstPage, LastPage
MediaCommands	Play, Pause, Stop, Record, NextTrack, PreviousTrack, FastForward, Rewind, ChannelUp, ChannelDown, TogglePlayPause, IncreaseVolume, DecreaseVolume, MuteVolume
EditingCommands	ToggleBold, ToggleItalic, ToggleUnderline, IncreaseFontSize, DecreaseFontSize, AlignLeft, AlignCenter, AlignRight, AlignJustify

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Advanced: See ADVANCED.md for custom RoutedCommand creation, keyboard/mouse event handling (PreviewKeyDown, drag logic), and FocusManager patterns.

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3. InputBinding (Keyboard/Mouse Shortcuts)

3.1 KeyBinding

<Window.InputBindings>
    <!-- Keyboard shortcut -->
    <KeyBinding Key="N" Modifiers="Control" Command="ApplicationCommands.New"/>
    <KeyBinding Key="S" Modifiers="Control" Command="ApplicationCommands.Save"/>
    <KeyBinding Key="S" Modifiers="Control+Shift" Command="ApplicationCommands.SaveAs"/>
    <KeyBinding Key="F4" Modifiers="Alt" Command="ApplicationCommands.Close"/>

    <!-- Function keys -->
    <KeyBinding Key="F1" Command="ApplicationCommands.Help"/>
    <KeyBinding Key="F5" Command="{x:Static cmd:CustomCommands.RefreshData}"/>

    <!-- MVVM Command binding -->
    <KeyBinding Key="Delete" Command="{Binding DeleteCommand}"/>
</Window.InputBindings>

3.2 MouseBinding

<Border.InputBindings>
    <!-- Double-click -->
    <MouseBinding MouseAction="LeftDoubleClick"
                  Command="{Binding OpenDetailCommand}"/>

    <!-- Middle click -->
    <MouseBinding MouseAction="MiddleClick"
                  Command="{Binding CloseTabCommand}"/>

    <!-- Ctrl + Left click -->
    <MouseBinding MouseAction="LeftClick"
                  Modifiers="Control"
                  Command="{Binding MultiSelectCommand}"/>
</Border.InputBindings>

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4. CommandParameter

4.1 Static Parameter

<Button Command="{Binding NavigateCommand}"
        CommandParameter="Home"
        Content="Go to Home"/>

<Button Command="{Binding SetZoomCommand}"
        CommandParameter="100"
        Content="Zoom 100%"/>

4.2 Binding Parameter

<ListBox x:Name="ItemList" ItemsSource="{Binding Items}"/>
<Button Command="{Binding DeleteCommand}"
        CommandParameter="{Binding SelectedItem, ElementName=ItemList}"
        Content="Delete Selected"/>

<!-- Self-reference -->
<Button Command="{Binding ProcessCommand}"
        CommandParameter="{Binding RelativeSource={RelativeSource Self}}"
        Content="Process This Button"/>

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5. CommandTarget

5.1 Redirecting Command Target

<StackPanel>
    <TextBox x:Name="TargetTextBox"/>

    <!-- Commands target the TextBox even when button is focused -->
    <Button Command="ApplicationCommands.Copy"
            CommandTarget="{Binding ElementName=TargetTextBox}"
            Content="Copy from TextBox"/>

    <Button Command="ApplicationCommands.Paste"
            CommandTarget="{Binding ElementName=TargetTextBox}"
            Content="Paste to TextBox"/>
</StackPanel>

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6. References

• Commanding Overview - Microsoft Docs
• Input Overview - Microsoft Docs
• Focus Overview - Microsoft Docs