ChangeNode.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 / Map / Update / Internal / ChangeNode.cs / 1305376 / ChangeNode.cs

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

using System.Data.Metadata.Edm; 
using System.Collections.Generic;
using System.Text;
using System.Globalization;
namespace System.Data.Mapping.Update.Internal 
{
    ///  
    /// This class encapsulates changes propagated to a node in an update mapping view. 
    /// It contains lists of deleted and inserted rows. Key intersections betweens rows
    /// in the two sets are treated as updates in the store. 
    /// 
    /// 
    /// 
    /// Additional tags indicating the roles of particular values (e.g., concurrency, undefined, 
    /// etc.) are stored within each row: where appropriate, constants appearing
    /// within a row are associated with a  through the . 
    /// 
    ///  
    /// The 'leaves' of an update mapping view (UMV) are extent expressions. A change node
    /// associated with an extent expression is simply the list of changes to the C-Space
    /// requested by a caller. As changes propagate 'up' the UMV expression tree, we recursively
    /// apply transformations such that the change node associated with the root of the UMV 
    /// represents changes to apply in the S-Space.
    ///  
    ///  
    internal class ChangeNode
    { 
        #region Constructors
        /// 
        /// Constructs a change node containing changes belonging to the specified collection
        /// schema definition. 
        /// 
        /// Sets  property. 
        internal ChangeNode(TypeUsage elementType) 
        {
            m_elementType = elementType; 
        }
        #endregion

        #region Fields 
        private TypeUsage m_elementType;
        private List m_inserted = new List(); 
        private List m_deleted = new List(); 
        private PropagatorResult m_placeholder;
        #endregion 

        #region Properties
        /// 
        /// Gets the type of the rows contained in this node. This type corresponds (not coincidentally) 
        /// to the type of an expression in an update mapping view.
        ///  
        internal TypeUsage ElementType { get { return m_elementType; } } 

        ///  
        /// Gets a list of rows to be inserted.
        /// 
        internal List Inserted { get { return m_inserted; } }
 
        /// 
        /// Gets a list of rows to be deleted. 
        ///  
        internal List Deleted { get { return m_deleted; } }
 
        /// 
        /// Gets or sets a version of a record at this node with default record. The record has the type
        /// of the node we are visiting.
        ///  
        internal PropagatorResult Placeholder
        { 
            get { return m_placeholder; } 
            set { m_placeholder = value; }
        } 
        #endregion

#if DEBUG
        public override string ToString() 
        {
            StringBuilder builder = new StringBuilder(); 
 
            builder.AppendLine("{");
            builder.AppendFormat(CultureInfo.InvariantCulture, "    ElementType = {0}", ElementType).AppendLine(); 
            builder.AppendLine("    Inserted = {");
            foreach (PropagatorResult insert in Inserted)
            {
                builder.Append("        ").AppendLine(insert.ToString()); 
            }
            builder.AppendLine("    }"); 
            builder.AppendLine("    Deleted = {"); 
            foreach (PropagatorResult delete in Deleted)
            { 
                builder.Append("        ").AppendLine(delete.ToString());
            }
            builder.AppendLine("    }");
            builder.AppendFormat(CultureInfo.InvariantCulture, "    PlaceHolder = {0}", Placeholder).AppendLine(); 

            builder.Append("}"); 
            return builder.ToString(); 
        }
#endif 
    }
}

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

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