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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.
using System.Collections;
using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Drawing;
using System.Globalization;
using System.Reflection;
namespace System.Windows.Forms;
/// <summary>
/// ListViewItemConverter is a class that can be used to convert
/// ListViewItem objects from one data type to another. Access this
/// class through the TypeDescriptor.
/// </summary>
public class ListViewItemConverter : ExpandableObjectConverter
{
/// <summary>
/// Gets a value indicating whether this converter can convert an object to the given
/// destination type using the context.
/// </summary>
public override bool CanConvertTo(ITypeDescriptorContext? context, Type? destinationType)
{
if (destinationType == typeof(InstanceDescriptor))
{
return true;
}
return base.CanConvertTo(context, destinationType);
}
/// <summary>
/// Converts the given object to another type. The most common types to convert
/// are to and from a string object. The default implementation will make a call
/// to ToString on the object if the object is valid and if the destination
/// type is string. If this cannot convert to the destination type, this will
/// throw a NotSupportedException.
/// </summary>
public override object? ConvertTo(ITypeDescriptorContext? context, CultureInfo? culture, object? value, Type destinationType)
{
ArgumentNullException.ThrowIfNull(destinationType);
if (destinationType == typeof(InstanceDescriptor) && value is ListViewItem item)
{
ConstructorInfo? ctor;
// Should we use the subitem constructor?
for (int i = 1; i < item.SubItems.Count; ++i)
{
if (item.SubItems[i].CustomStyle)
{
if (!string.IsNullOrEmpty(item.ImageKey))
{
ctor = typeof(ListViewItem).GetConstructor([typeof(ListViewItem.ListViewSubItem[]), typeof(string)]);
Debug.Assert(ctor is not null, "Expected the constructor to exist.");
ListViewItem.ListViewSubItem[] subItemArray = new ListViewItem.ListViewSubItem[item.SubItems.Count];
((ICollection)item.SubItems).CopyTo(subItemArray, 0);
return new InstanceDescriptor(ctor, new object[] { subItemArray, item.ImageKey }, false);
}
else
{
ctor = typeof(ListViewItem).GetConstructor([typeof(ListViewItem.ListViewSubItem[]), typeof(int)]);
Debug.Assert(ctor is not null, "Expected the constructor to exist.");
ListViewItem.ListViewSubItem[] subItemArray = new ListViewItem.ListViewSubItem[item.SubItems.Count];
((ICollection)item.SubItems).CopyTo(subItemArray, 0);
return new InstanceDescriptor(ctor, new object[] { subItemArray, item.ImageIndex }, false);
}
}
}
// Convert SubItem array to string array
string[] subItems = new string[item.SubItems.Count];
for (int i = 0; i < subItems.Length; ++i)
{
subItems[i] = item.SubItems[i].Text;
}
// ForeColor, BackColor or ItemFont set
if (item.SubItems[0].CustomStyle)
{
if (!string.IsNullOrEmpty(item.ImageKey))
{
ctor = typeof(ListViewItem).GetConstructor(
[
typeof(string[]),
typeof(string),
typeof(Color),
typeof(Color),
typeof(Font)
]);
Debug.Assert(ctor is not null, "Expected the constructor to exist.");
return new InstanceDescriptor(ctor, new object?[]
{
subItems,
item.ImageKey,
item.SubItems[0].CustomForeColor ? item.ForeColor : Color.Empty,
item.SubItems[0].CustomBackColor ? item.BackColor : Color.Empty,
item.SubItems[0].CustomFont ? item.Font : null
}, false);
}
else
{
ctor = typeof(ListViewItem).GetConstructor(
[
typeof(string[]),
typeof(int),
typeof(Color),
typeof(Color),
typeof(Font)
]);
Debug.Assert(ctor is not null, "Expected the constructor to exist.");
return new InstanceDescriptor(ctor, new object?[]
{
subItems,
item.ImageIndex,
item.SubItems[0].CustomForeColor ? item.ForeColor : Color.Empty,
item.SubItems[0].CustomBackColor ? item.BackColor : Color.Empty,
item.SubItems[0].CustomFont ? item.Font : null
}, false);
}
}
// Text
if (item.ImageIndex == -1 && string.IsNullOrEmpty(item.ImageKey) && item.SubItems.Count <= 1)
{
ctor = typeof(ListViewItem).GetConstructor([typeof(string)]);
Debug.Assert(ctor is not null, "Expected the constructor to exist.");
return new InstanceDescriptor(ctor, new object[] { item.Text }, false);
}
// Text and Image
if (item.SubItems.Count <= 1)
{
if (!string.IsNullOrEmpty(item.ImageKey))
{
ctor = typeof(ListViewItem).GetConstructor(
[
typeof(string),
typeof(string)
]);
Debug.Assert(ctor is not null, "Expected the constructor to exist.");
return new InstanceDescriptor(ctor, new object[] { item.Text, item.ImageKey }, false);
}
else
{
ctor = typeof(ListViewItem).GetConstructor(
[
typeof(string),
typeof(int)
]);
Debug.Assert(ctor is not null, "Expected the constructor to exist.");
return new InstanceDescriptor(ctor, new object[] { item.Text, item.ImageIndex }, false);
}
}
// Text, Image and SubItems
if (!string.IsNullOrEmpty(item.ImageKey))
{
ctor = typeof(ListViewItem).GetConstructor(
[
typeof(string[]),
typeof(string)
]);
Debug.Assert(ctor is not null, "Expected the constructor to exist.");
return new InstanceDescriptor(ctor, new object[] { subItems, item.ImageKey }, false);
}
else
{
ctor = typeof(ListViewItem).GetConstructor(
[
typeof(string[]),
typeof(int)
]);
return new InstanceDescriptor(ctor, new object[] { subItems, item.ImageIndex }, false);
}
}
return base.ConvertTo(context, culture, value, destinationType);
}
}
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