EntityAdapter.cs source code in C# .NET

                        Code:
                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / fx / src / DataEntity / System / Data / EntityClient / EntityAdapter.cs / 1305376 / EntityAdapter.cs
                        
                        
                            //---------------------------------------------------------------------- 
// 
//      Copyright (c) Microsoft Corporation.  All rights reserved.
// 
// 
// @owner  [....]
// @backupOwner [....] 
//--------------------------------------------------------------------- 
using System.Collections.Generic;
using System.Text; 
using System.Data;
using System.Data.Common;
using System.Data.Mapping.Update.Internal;
using System.Data.Objects; 
using System.Diagnostics;
using System.Data.Mapping; 
 
namespace System.Data.EntityClient
{ 
    /// 
    /// Class representing a data adapter for the conceptual layer
    /// 
    internal sealed class EntityAdapter : IEntityAdapter 
    {
        private bool _acceptChangesDuringUpdate = true; 
        private EntityConnection _connection; 
        private Int32? _commandTimeout;
 
        /// 
        /// Constructs the EntityAdapter object without a connection object
        /// 
        public EntityAdapter() 
        {
        } 
 
        /// 
        /// Gets or sets the map connection used by this adapter. 
        /// 
        DbConnection IEntityAdapter.Connection
        {
            get 
            {
                return this.Connection; 
            } 
            set
            { 
                this.Connection = (EntityConnection)value;
            }
        }
 
        /// 
        /// Gets or sets the map connection used by this adapter. 
        ///  
        public EntityConnection Connection
        { 
            get
            {
                return _connection;
            } 
            set
            { 
                _connection = value; 
            }
        } 

        /// 
        /// Gets or sets whether the IEntityCache.AcceptChanges should be called during a call to IEntityAdapter.Update.
        ///  
        public bool AcceptChangesDuringUpdate
        { 
            get 
            {
                return this._acceptChangesDuringUpdate; 
            }
            set
            {
                this._acceptChangesDuringUpdate = value; 
            }
        } 
 
        /// 
        /// Gets of sets the command timeout for update operations. If null, indicates that the default timeout 
        /// for the provider should be used.
        /// 
        Int32? IEntityAdapter.CommandTimeout
        { 
            get
            { 
                return this._commandTimeout; 
            }
            set 
            {
                this._commandTimeout = value;
            }
        } 

        ///  
        /// Persist modifications described in the given cache. 
        /// 
        /// Entity cache containing changes to persist to the store. 
        /// Number of cache entries affected by the udpate.
        public Int32 Update(IEntityStateManager entityCache)
        {
            EntityUtil.CheckArgumentNull(entityCache, "entityCache"); 
            if (!IsStateManagerDirty(entityCache)) { return 0; }
 
            // Check that we have a connection before we proceed 
            if (_connection == null)
            { 
                throw EntityUtil.InvalidOperation(System.Data.Entity.Strings.EntityClient_NoConnectionForAdapter);
            }

            // Check that the store connection is available 
            if (_connection.StoreProviderFactory == null || this._connection.StoreConnection == null)
            { 
                throw EntityUtil.InvalidOperation(System.Data.Entity.Strings.EntityClient_NoStoreConnectionForUpdate); 
            }
 
            // Check that the connection is open before we proceed
            if (ConnectionState.Open != _connection.State)
            {
                throw EntityUtil.InvalidOperation(System.Data.Entity.Strings.EntityClient_ClosedConnectionForUpdate); 
            }
 
            return UpdateTranslator.Update(entityCache, this); 
        }
 
        /// 
        /// Determine whether the cache has changes to apply.
        /// 
        /// ObjectStateManager to check. Must not be null. 
        /// true if cache contains changes entries; false otherwise
        private static bool IsStateManagerDirty(IEntityStateManager entityCache) 
        { 
            Debug.Assert(null != entityCache);
            bool hasChanges = false; 
            // this call to GetCacheEntries is constant time (the ObjectStateManager implementation
            // maintains an explicit list of entries in each state)
            foreach (ObjectStateEntry entry in entityCache.GetEntityStateEntries(
                EntityState.Added | EntityState.Deleted | EntityState.Modified)) 
            {
                hasChanges = true; 
                break; 
            }
            return hasChanges; 
        }
    }
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
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EntityAdapter.cs source code in C# .NET

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