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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.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Diagnostics.CodeAnalysis;
using System.Globalization;
namespace System.Data
{
internal sealed class ConstraintConverter : ExpandableObjectConverter
{
// converter classes should have public ctor
public ConstraintConverter() { }
/// <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, [NotNullWhen(true)] Type? destinationType) =>
destinationType == typeof(InstanceDescriptor) ||
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 Constraint)
{
if (value is UniqueConstraint)
{
UniqueConstraint constr = (UniqueConstraint)value;
Reflection.ConstructorInfo ctor = typeof(UniqueConstraint).GetConstructor(new Type[] { typeof(string), typeof(string[]), typeof(bool) })!;
if (ctor != null)
{
return new InstanceDescriptor(ctor, new object[] { constr.ConstraintName, constr.ColumnNames, constr.IsPrimaryKey });
}
}
else
{
ForeignKeyConstraint constr = (ForeignKeyConstraint)value;
System.Reflection.ConstructorInfo ctor =
typeof(ForeignKeyConstraint).GetConstructor(new Type[] { typeof(string), typeof(string), typeof(string[]),
typeof(string[]), typeof(AcceptRejectRule), typeof(Rule), typeof(Rule) })!;
if (ctor != null)
{
return new InstanceDescriptor(ctor, new object[] { constr.ConstraintName, constr.ParentKey.Table.TableName, constr.ParentColumnNames,
constr.ChildColumnNames, constr.AcceptRejectRule, constr.DeleteRule, constr.UpdateRule });
}
}
}
return base.ConvertTo(context, culture, value, destinationType);
}
}
}
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