| File: System\Windows\Forms\Controls\ListView\ColumnHeaderConverter.cs | Web Access |
| Project: src\winforms\src\System.Windows.Forms\System.Windows.Forms.csproj (System.Windows.Forms) |
// Licensed to the .NET Foundation under one or more agreements. // The .NET Foundation licenses this file to you under the MIT license. using System.ComponentModel; using System.ComponentModel.Design.Serialization; using System.Globalization; using System.Reflection; namespace System.Windows.Forms; public class ColumnHeaderConverter : 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 ColumnHeader col) { ConstructorInfo? ctor; Type t = TypeDescriptor.GetReflectionType(value); InstanceDescriptor? id = null; if (col.ImageIndex != -1) { ctor = t.GetConstructor([typeof(int)]); if (ctor is not null) { id = new InstanceDescriptor(ctor, new object[] { col.ImageIndex }, false); } } if (id is null && !string.IsNullOrEmpty(col.ImageKey)) { ctor = t.GetConstructor([typeof(string)]); if (ctor is not null) { id = new InstanceDescriptor(ctor, new object[] { col.ImageKey }, false); } } if (id is null) { ctor = t.GetConstructor([]); if (ctor is not null) { return new InstanceDescriptor(ctor, Array.Empty<object>(), false); } else { throw new ArgumentException(string.Format(SR.NoDefaultConstructor, t.FullName)); } } return id; } return base.ConvertTo(context, culture, value, destinationType); } }