RelationshipConverter.cs

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using System.ComponentModel;
using System.ComponentModel.Design.Serialization;
using System.Globalization;
using System.Reflection;
 
namespace System.Data;
 
internal sealed class RelationshipConverter : ExpandableObjectConverter
{
    public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType)
    {
        if (destinationType == typeof(InstanceDescriptor))
        {
            return true;
        }
        return base.CanConvertTo(context, destinationType);
    }
 
    public override object ConvertTo(ITypeDescriptorContext context, CultureInfo culture, object value, Type destinationType)
    {
        if (destinationType == null)
        {
            throw new ArgumentNullException("destinationType");
        }
        ConstructorInfo constructorInfo = null;
        object[] array = null;
        if (destinationType == typeof(InstanceDescriptor) && value is DataRelation)
        {
            DataRelation dataRelation = (DataRelation)value;
            DataTable table = dataRelation.ParentKey.Table;
            DataTable table2 = dataRelation.ChildKey.Table;
            if (string.IsNullOrEmpty(table.Namespace) && string.IsNullOrEmpty(table2.Namespace))
            {
                constructorInfo = typeof(DataRelation).GetConstructor(new Type[6]
                {
                    typeof(string),
                    typeof(string),
                    typeof(string),
                    typeof(string[]),
                    typeof(string[]),
                    typeof(bool)
                });
                array = new object[6]
                {
                    dataRelation.RelationName,
                    dataRelation.ParentKey.Table.TableName,
                    dataRelation.ChildKey.Table.TableName,
                    dataRelation.ParentColumnNames,
                    dataRelation.ChildColumnNames,
                    dataRelation.Nested
                };
            }
            else
            {
                constructorInfo = typeof(DataRelation).GetConstructor(new Type[8]
                {
                    typeof(string),
                    typeof(string),
                    typeof(string),
                    typeof(string),
                    typeof(string),
                    typeof(string[]),
                    typeof(string[]),
                    typeof(bool)
                });
                array = new object[8]
                {
                    dataRelation.RelationName,
                    dataRelation.ParentKey.Table.TableName,
                    dataRelation.ParentKey.Table.Namespace,
                    dataRelation.ChildKey.Table.TableName,
                    dataRelation.ChildKey.Table.Namespace,
                    dataRelation.ParentColumnNames,
                    dataRelation.ChildColumnNames,
                    dataRelation.Nested
                };
            }
            return new InstanceDescriptor(constructorInfo, array);
        }
        return base.ConvertTo(context, culture, value, destinationType);
    }
}