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//------------------------------------------------------------------------------
// <copyright file="ConstraintConverter.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
// <owner current="true" primary="true">Microsoft</owner>
// <owner current="true" primary="false">Microsoft</owner>
// <owner current="false" primary="false">Microsoft</owner>
//------------------------------------------------------------------------------
namespace System.Data {
using System;
using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Globalization;
/// <devdoc>
/// </devdoc>
sealed internal class ConstraintConverter : ExpandableObjectConverter {
// converter classes should have public ctor
public ConstraintConverter() {
}
/// <devdoc>
/// <para>Gets a value indicating whether this converter can
/// convert an object to the given destination type using the context.</para>
/// </devdoc>
public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType) {
if (destinationType == typeof(InstanceDescriptor)) {
return true;
}
return base.CanConvertTo(context, destinationType);
}
/// <devdoc>
/// 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 desitnation type, this will
/// throw a NotSupportedException.
/// </devdoc>
public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType) {
if (destinationType == null) {
throw new ArgumentNullException("destinationType");
}
if (destinationType == typeof(InstanceDescriptor) && value is Constraint) {
if (value is UniqueConstraint) {
UniqueConstraint constr = (UniqueConstraint)value;
System.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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