|
//------------------------------------------------------------------------------
// <copyright file="RelationshipConverter.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;
sealed internal class RelationshipConverter : ExpandableObjectConverter {
// converter classes should have public ctor
public RelationshipConverter() {
}
/// <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");
}
System.Reflection.ConstructorInfo ctor = null;
object[] values = null;
if (destinationType == typeof(InstanceDescriptor) && value is DataRelation) {
DataRelation rel = (DataRelation) value;
DataTable parentTable = rel.ParentKey.Table;
DataTable childTable = rel.ChildKey.Table;
if (System.Data.Common.ADP.IsEmpty(parentTable.Namespace) && System.Data.Common.ADP.IsEmpty(childTable.Namespace)) {
ctor = typeof(DataRelation).GetConstructor(new Type[] { typeof(string) /*relationName*/, typeof(string) /*parentTableName*/, typeof(string) /*childTableName */,
typeof(string[]) /*parentColumnNames */, typeof(string[]) /*childColumnNames*/, typeof(bool) /*nested*/ } );
values = new object[] { rel.RelationName, rel.ParentKey.Table.TableName, rel.ChildKey.Table.TableName,rel.ParentColumnNames, rel.ChildColumnNames, rel.Nested };
}
else {
ctor = typeof(DataRelation).GetConstructor(new Type[] { typeof(string)/*relationName*/, typeof(string)/*parentTableName*/, typeof(string)/*parentTableNamespace*/,
typeof(string)/*childTableName */, typeof(string)/*childTableNamespace */,
typeof(string[])/*parentColumnNames */, typeof(string[]) /*childColumnNames*/, typeof(bool) /*nested*/} );
values = new object[] { rel.RelationName, rel.ParentKey.Table.TableName, rel.ParentKey.Table.Namespace, rel.ChildKey.Table.TableName,
rel.ChildKey.Table.Namespace, rel.ParentColumnNames, rel.ChildColumnNames, rel.Nested };
}
return new InstanceDescriptor(ctor, values);
}
return base.ConvertTo(context, culture, value, destinationType);
}
}
}
|