WPF Clipboard Patterns

Implementing copy/paste functionality using the Windows clipboard.

Advanced Patterns: See ADVANCED.md for clipboard monitoring and error handling.

1. Clipboard Overview

Clipboard Operations ├── Text Operations │ ├── SetText / GetText │ └── Unicode, RTF, HTML support ├── Image Operations │ ├── SetImage / GetImage │ └── BitmapSource support ├── File Operations │ ├── SetFileDropList / GetFileDropList │ └── File path collection └── Custom Data ├── SetData / GetData └── DataObject with multiple formats

2. Text Operations

2.1 Basic Text Copy/Paste

using System.Windows;

// Copy text to clipboard Clipboard.SetText("Hello, World!");

// Paste text from clipboard if (Clipboard.ContainsText()) { var text = Clipboard.GetText(); // Use text }

2.2 Text Formats

// Set text with specific format Clipboard.SetText("Hello", TextDataFormat.UnicodeText); Clipboard.SetText("<b>Hello</b>", TextDataFormat.Html); Clipboard.SetText(@"{\rtf1 Hello}", TextDataFormat.Rtf);

// Get text with specific format if (Clipboard.ContainsText(TextDataFormat.Html)) { var html = Clipboard.GetText(TextDataFormat.Html); }

TextDataFormat Options:

Value Description

Text ANSI text

UnicodeText Unicode text (default)

Rtf Rich Text Format

Html HTML format

CommaSeparatedValue CSV format

3. Image Operations

3.1 Copy/Paste Images

using System.Windows; using System.Windows.Media.Imaging;

// Copy image to clipboard var bitmap = new BitmapImage(new Uri("pack://application:,,,/Images/logo.png")); Clipboard.SetImage(bitmap);

// Paste image from clipboard if (Clipboard.ContainsImage()) { var image = Clipboard.GetImage(); MyImage.Source = image; }

3.2 Copy UI Element as Image

using System.Windows.Media; using System.Windows.Media.Imaging;

public static void CopyElementAsImage(FrameworkElement element) { var width = (int)element.ActualWidth; var height = (int)element.ActualHeight;

var renderBitmap = new RenderTargetBitmap(
    width, height, 96, 96, PixelFormats.Pbgra32);

renderBitmap.Render(element);
Clipboard.SetImage(renderBitmap);

}

4. File Operations

4.1 Copy/Paste File Paths

using System.Collections.Specialized; using System.Windows;

// Copy files to clipboard var files = new StringCollection { @"C:\Documents\file1.txt", @"C:\Documents\file2.txt" }; Clipboard.SetFileDropList(files);

// Paste files from clipboard if (Clipboard.ContainsFileDropList()) { var fileList = Clipboard.GetFileDropList();

foreach (var file in fileList)
{
    ProcessFile(file);
}

}

5. DataObject (Multiple Formats)

5.1 Setting Multiple Formats

public static void CopyWithMultipleFormats(MyDataItem item) { var dataObject = new DataObject();

// Add multiple formats for compatibility
dataObject.SetData(DataFormats.Text, item.ToString());
dataObject.SetData(DataFormats.Html, item.ToHtml());
dataObject.SetData(typeof(MyDataItem), item);

Clipboard.SetDataObject(dataObject);

}

5.2 Getting Data by Format

public static void PasteData() { var dataObject = Clipboard.GetDataObject();

if (dataObject == null)
    return;

// Check available formats
var formats = dataObject.GetFormats();

// Try custom format first
if (dataObject.GetDataPresent(typeof(MyDataItem)))
{
    var item = dataObject.GetData(typeof(MyDataItem)) as MyDataItem;
    ProcessItem(item);
    return;
}

// Fall back to text
if (dataObject.GetDataPresent(DataFormats.Text))
{
    var text = dataObject.GetData(DataFormats.Text) as string;
    ProcessText(text);
}

}

5.3 Keeping Data After App Close

// Data persists after application closes Clipboard.SetDataObject(dataObject, copy: true);

// Data is removed when application closes (default) Clipboard.SetDataObject(dataObject, copy: false);

6. Custom Data Formats

6.1 Registering Custom Format

public static class CustomClipboardFormats { public static readonly string MyAppItemFormat = DataFormats.GetDataFormat("MyApp.CustomItem").Name; }

6.2 Using Custom Format

// Copy with custom format var dataObject = new DataObject(); dataObject.SetData(CustomClipboardFormats.MyAppItemFormat, myItem); Clipboard.SetDataObject(dataObject);

// Paste with custom format var data = Clipboard.GetDataObject();

if (data?.GetDataPresent(CustomClipboardFormats.MyAppItemFormat) == true) { var item = data.GetData(CustomClipboardFormats.MyAppItemFormat) as MyItem; }

7. Clipboard with Commands

7.1 Built-in Commands

<TextBox x:Name="MyTextBox"/>

<!-- Built-in clipboard commands work automatically --> <Button Command="ApplicationCommands.Cut" CommandTarget="{Binding ElementName=MyTextBox}" Content="Cut"/> <Button Command="ApplicationCommands.Copy" CommandTarget="{Binding ElementName=MyTextBox}" Content="Copy"/> <Button Command="ApplicationCommands.Paste" CommandTarget="{Binding ElementName=MyTextBox}" Content="Paste"/>

7.2 Custom Clipboard Commands

namespace MyApp.ViewModels;

using System.Windows; using CommunityToolkit.Mvvm.ComponentModel; using CommunityToolkit.Mvvm.Input;

public partial class MainViewModel : ObservableObject { [ObservableProperty] private MyItem? _selectedItem;

[RelayCommand(CanExecute = nameof(CanCopy))]
private void Copy()
{
    if (SelectedItem == null)
        return;

    var dataObject = new DataObject();
    dataObject.SetData(typeof(MyItem), SelectedItem);
    dataObject.SetData(DataFormats.Text, SelectedItem.ToString());

    Clipboard.SetDataObject(dataObject, copy: true);
}

private bool CanCopy() => SelectedItem != null;

[RelayCommand(CanExecute = nameof(CanPaste))]
private void Paste()
{
    var data = Clipboard.GetDataObject();

    if (data?.GetDataPresent(typeof(MyItem)) == true)
    {
        var item = data.GetData(typeof(MyItem)) as MyItem;

        if (item != null)
        {
            Items.Add(item.Clone());
        }
    }
}

private bool CanPaste() => Clipboard.ContainsData(typeof(MyItem).FullName!);

}

8. References

• Clipboard Class - Microsoft Docs

• DataObject Class - Microsoft Docs

• How to: Use the Clipboard - Microsoft Docs