ObjectStateEntryOriginalDbUpdatableDataRecord.cs source code in C# .NET

Source code for the .NET framework in C#

                        

Code:

/ 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / DataEntity / System / Data / Objects / ObjectStateEntryOriginalDbUpdatableDataRecord.cs / 1305376 / ObjectStateEntryOriginalDbUpdatableDataRecord.cs

                            //---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// 
// @owner       [....]
// @backupOwner [....] 
//--------------------------------------------------------------------- 
using System;
using System.ComponentModel; 
using System.Data;
using System.Data.Common;
using System.Data.Metadata.Edm;
using System.Diagnostics; 
using System.Reflection;
 
namespace System.Data.Objects 
{
    // Internal version of writeable original values record is used by all internal operations that need to set original values, such as PreserveChanges queries 
    // This version should never be returned to the user, because it doesn't enforce any necessary restrictions.
    // See ObjectStateEntryOriginalDbUpdatableDataRecord_Public for user scenarios.
    internal class ObjectStateEntryOriginalDbUpdatableDataRecord_Internal : OriginalValueRecord
    { 
        internal ObjectStateEntryOriginalDbUpdatableDataRecord_Internal(EntityEntry cacheEntry, StateManagerTypeMetadata metadata, object userObject)
            : base(cacheEntry, metadata, userObject) 
        { 
            EntityUtil.CheckArgumentNull(cacheEntry, "cacheEntry");
            EntityUtil.CheckArgumentNull(userObject, "userObject"); 
            EntityUtil.CheckArgumentNull(metadata, "metadata");
            Debug.Assert(!cacheEntry.IsKeyEntry, "Cannot create an ObjectStateEntryOriginalDbUpdatableDataRecord_Internal for a key entry");
            switch (cacheEntry.State)
            { 
                case EntityState.Unchanged:
                case EntityState.Modified: 
                case EntityState.Deleted: 
                    break;
                default: 
                    Debug.Assert(false, "An OriginalValueRecord cannot be created for an object in an added or detached state.");
                    break;
            }
        } 
        protected override object GetRecordValue(int ordinal)
        { 
            Debug.Assert(!_cacheEntry.IsRelationship, "should not be relationship"); 
            return (_cacheEntry as EntityEntry).GetOriginalEntityValue(_metadata, ordinal, _userObject, ObjectStateValueRecord.OriginalUpdatableInternal);
        } 
        protected override void SetRecordValue(int ordinal, object value)
        {
            Debug.Assert(!_cacheEntry.IsRelationship, "should not be relationship");
            (_cacheEntry as EntityEntry).SetOriginalEntityValue(_metadata, ordinal, _userObject, value); 
        }
    } 
 
    // Public version of writeble original values record that is to be returned to the user for setting original values directly.
    // Although this class is actually internal, it is the version that implements the writeable original values functionality returned through the public surface. 
    // This version must maintain information about the index of the top-level entity property that corresponds to this record, because the record
    // may represent a complex type somewhere in an entity hierarchy and this is the only way we know which entity property it is associated with.
    // This version also does minimal necessary validation on the values that the user is trying to set.
    internal sealed class ObjectStateEntryOriginalDbUpdatableDataRecord_Public : ObjectStateEntryOriginalDbUpdatableDataRecord_Internal 
    {
        // Will be EntityEntry.s_EntityRoot for entities and for complex types will be the index of the top-level entity property related to this complex type 
        int _parentEntityPropertyIndex; 

        internal ObjectStateEntryOriginalDbUpdatableDataRecord_Public(EntityEntry cacheEntry, StateManagerTypeMetadata metadata, object userObject, int parentEntityPropertyIndex) 
            : base(cacheEntry, metadata, userObject)
        {
            _parentEntityPropertyIndex = parentEntityPropertyIndex;
        } 

        protected override object GetRecordValue(int ordinal) 
        { 
            Debug.Assert(!_cacheEntry.IsRelationship, "should not be relationship");
            return (_cacheEntry as EntityEntry).GetOriginalEntityValue(_metadata, ordinal, _userObject, ObjectStateValueRecord.OriginalUpdatablePublic, GetPropertyIndex(ordinal)); 
        }

        protected override void SetRecordValue(int ordinal, object value)
        { 
            StateManagerMemberMetadata member = _metadata.Member(ordinal);
 
            // We do not allow setting complex properties through writeable original values. 
            // Instead individual scalar properties can be set on a data record that represents the complex type.
            if (member.IsComplex) 
            {
                throw EntityUtil.SetOriginalComplexProperties(member.CLayerName);
            }
 
            // Null values are represented in data records as DBNull.Value, so translate appropriately
            object fieldValue = value ?? DBNull.Value; 
 
            EntityEntry entry = _cacheEntry as EntityEntry;
            EntityState oldState = entry.State; 

            // Only update the original values if the new value is different from the value currently set on the entity
            if (entry.HasRecordValueChanged(this, ordinal, fieldValue))
            { 
                // Since the original value is going to be set, validate that is doesn't violate any restrictions
 
                // Throw if trying to change the original value of the primary key 
                if (member.IsPartOfKey)
                { 
                    throw EntityUtil.SetOriginalPrimaryKey(member.CLayerName);
                }

                // Verify non-nullable CLR types are not being set to null 
                // Checking CLR type compatibility only because that's all that we check elsewhere in the stack for setting property values
                Type memberClrType = member.ClrType; 
                if ((object)DBNull.Value == fieldValue && memberClrType.IsValueType && 
                    !(memberClrType.IsGenericType && typeof(Nullable<>) == memberClrType.GetGenericTypeDefinition()))
                { 
                    // Throw if the underlying CLR type of this property is not nullable, and it is being set to null
                    throw EntityUtil.NullOriginalValueForNonNullableProperty(member.CLayerName, member.ClrMetadata.Name, member.ClrMetadata.DeclaringType.FullName);
                }
 
                base.SetRecordValue(ordinal, value);
 
                // Update the state of the ObjectStateEntry if it has been marked as Modified 
                if (oldState == EntityState.Unchanged && entry.State == EntityState.Modified)
                { 
                    entry.ObjectStateManager.ChangeState(entry, oldState, EntityState.Modified);
                }

                // Set the individual property to modified 
                entry.SetModifiedPropertyInternal(GetPropertyIndex(ordinal));
            } 
        } 

        // For entities the property index is the specified ordinal, but otherwise it's the top-level entity property index that we have saved 
        private int GetPropertyIndex(int ordinal)
        {
            return _parentEntityPropertyIndex == EntityEntry.s_EntityRoot ? ordinal : _parentEntityPropertyIndex;
        } 
    }
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
                        

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