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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
//
//
//
// Description: TextDecorationCollection class
//
//
using System.Collections;
using System.ComponentModel;
using System.Windows.Media.Animation;
namespace System.Windows
{
/// <summary>
/// A collection of text decoration instances
/// </summary>
[TypeConverter(typeof(TextDecorationCollectionConverter))]
[Localizability(LocalizationCategory.None, Readability=Readability.Unreadable)]
public sealed partial class TextDecorationCollection : Animatable, IList
{
/// <summary>
/// Compare this collection with another TextDecorations.
/// </summary>
/// <param name="textDecorations"> the text decoration collection to be compared </param>
/// <returns> true if two collections of TextDecorations contain equal TextDecoration objects in the
/// the same order. false otherwise
/// </returns>
/// <remarks>
/// The method doesn't check "full" equality as it can not take into account of all the possible
/// values associated with the DependencyObject,such as Animation, DataBinding and Attached property.
/// It only compares the public properties to serve the specific Framework's needs in inline property
/// management and Editing serialization.
/// </remarks>
internal bool ValueEquals(TextDecorationCollection textDecorations)
{
if (textDecorations == null)
return false; // o is either null or not TextDecorations object
if (this == textDecorations)
return true; // Reference equality.
if ( this.Count != textDecorations.Count)
return false; // Two counts are different.
// To be considered equal, TextDecorations should be same in the exact order.
// Order matters because they imply the Z-order of the text decorations on screen.
// Same set of text decorations drawn with different orders may have different result.
for (int i = 0; i < this.Count; i++)
{
if (!this[i].ValueEquals(textDecorations[i]))
return false;
}
return true;
}
/// <summary>
/// Add a collection of text decorations into the current collection
/// </summary>
/// <param name="textDecorations"> The collection to be added </param>
[CLSCompliant(false)]
public void Add(IEnumerable<TextDecoration> textDecorations)
{
ArgumentNullException.ThrowIfNull(textDecorations);
foreach (TextDecoration textDecoration in textDecorations)
{
Add(textDecoration);
}
}
/// <summary>
/// Remove a collection of text decorations from the current collection and return
/// the resultant (new) collection. The current collection remains unchanged. If the collection
/// to be removed is not a subset of the current collection, then no element is removed. If
/// the source collection has multiple instances of an item, then all intances of the item is
/// removed.
/// </summary>
/// <param name="textDecorations">The collection to be removed</param>
/// <param name="result">
/// Out parameter containing the result. If no element was removed
/// from the current collection, then result is a new (unfrozen) collection
/// identical to the original one.
/// </param>
/// <returns>True if at least one item was removed from the current collection, False otherwise</returns>
public bool TryRemove(IEnumerable<TextDecoration> textDecorations, out TextDecorationCollection result)
{
ArgumentNullException.ThrowIfNull(textDecorations);
bool removed = false;
result = this.Clone(); //the current collection might be frozen, so clone it
foreach (TextDecoration textDecoration in textDecorations)
{
for (int i = result.Count -1; i >= 0; --i)
{
if (result[i].ValueEquals(textDecoration))
{
result.RemoveAt(i);
removed = true;
}
}
}
return removed;
}
}
}
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