ConstraintConverter.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / DotNET / DotNET / 8.0 / untmp / whidbey / REDBITS / ndp / fx / src / Data / System / Data / ConstraintConverter.cs / 1 / ConstraintConverter.cs
                        

                        
                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// [....] 
// [....]
// [....] 
//----------------------------------------------------------------------------- 

namespace System.Data { 
    using System;
    using System.ComponentModel;
    using System.ComponentModel.Design.Serialization;
    using System.Globalization; 

    ///  
    ///  
    sealed internal class ConstraintConverter : ExpandableObjectConverter {
 
        // converter classes should have public ctor
        public ConstraintConverter() {
        }
 
        /// 
        ///    Gets a value indicating whether this converter can 
        ///       convert an object to the given destination type using the context. 
        /// 
        public override bool CanConvertTo(ITypeDescriptorContext context, Type destinationType) { 
            if (destinationType == typeof(InstanceDescriptor)) {
                return true;
            }
            return base.CanConvertTo(context, destinationType); 
        }
 
        ///  
        ///      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.
        ///  
        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); 
        }
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

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