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//---------------------------------------------------------------------------
//
// <copyright file="DataObjectEventArgs.cs" company="Microsoft">
// Copyright (C) Microsoft Corporation. All rights reserved.
// </copyright>
//
// Description: Base class for DataObject events arguments
//
//---------------------------------------------------------------------------
using System;
namespace System.Windows
{
/// <summary>
/// Base class for DataObject.Copying/Pasting events.
/// These events are raised when an editor deals with
/// a data object before putting it to clipboard on copy
/// and before starting drag operation;
/// or before Pasting its content into a selection
/// on Paste/Drop operations.
///
/// This class is abstract - it provides only common
/// members for the events. Particular commands
/// must use more specific event arguments -
/// DataObjectCopyingEventArgs or DataObjectPastingEventArgs.
/// </summary>
public abstract class DataObjectEventArgs : RoutedEventArgs
{
//------------------------------------------------------
//
// Constructors
//
//------------------------------------------------------
#region Constructors
/// <summary>
/// Creates a DataObjectCopyEvent.
/// This object created by editors executing a Copy/Paste
/// and Drag/Drop comands.
/// </summary>
/// <param name="routedEvent">
/// An event id. One of: CopyingEvent or PastingEvent
/// </param>
/// <param name="isDragDrop">
/// A flag indicating if this operation is part of drag/drop.
/// Copying event fired on drag start, Pasting - on drop.
/// Cancelling the command stops drag/drop process in
/// an appropriate moment.
/// </param>
internal DataObjectEventArgs(RoutedEvent routedEvent, bool isDragDrop) : base()
{
if (routedEvent != DataObject.CopyingEvent && routedEvent != DataObject.PastingEvent && routedEvent != DataObject.SettingDataEvent)
{
throw new ArgumentOutOfRangeException("routedEvent");
}
RoutedEvent = routedEvent;
_isDragDrop = isDragDrop;
_commandCancelled = false;
}
#endregion Constructors
//------------------------------------------------------
//
// Public Properties
//
//------------------------------------------------------
#region Public Properties
/// <summary>
/// A flag indicating if this operation is part of drag/drop.
/// Copying event fired on drag start, Pasting - on drop.
/// Cancelling the command stops drag/drop process in
/// an appropriate moment.
/// </summary>
public bool IsDragDrop
{
get { return _isDragDrop; }
}
/// <summary>
/// A current cancellation status of the event.
/// When set to true, copy command is going to be cancelled.
/// </summary>
public bool CommandCancelled
{
get { return _commandCancelled; }
}
#endregion Public Properties
//------------------------------------------------------
//
// Protected Methods
//
//------------------------------------------------------
#region Public Methods
/// <summary>
/// Sets cancelled status of a command to true.
/// After calling this method the command will be
/// stopped from calling.
/// Applied to Drag (event="Copying", isDragDrop="true")
/// this would stop the whole dragdrop process.
/// </summary>
/// <remarks>
/// After an event has been cancelled it's impossible
/// to re-enable it.
/// </remarks>
public void CancelCommand()
{
_commandCancelled = true;
}
#endregion Public Methods
//------------------------------------------------------
//
// Private Fields
//
//------------------------------------------------------
#region Private Fields
private bool _isDragDrop;
private bool _commandCancelled;
#endregion Private Fields
}
}
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