DrawingCollection.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / DotNET / DotNET / 8.0 / untmp / WIN_WINDOWS / lh_tools_devdiv_wpf / Windows / wcp / Core / System / Windows / Media / DrawingCollection.cs / 1 / DrawingCollection.cs
                        

                        
                            //---------------------------------------------------------------------------- 
//
// Copyright (c) Microsoft Corporation.  All rights reserved.
//
// Description: This file contains non-generated DrawingCollection 
//              methods.
// 
// History: 
//
//  2005/03/18 : [....] - Created it. 
//
//---------------------------------------------------------------------------

using System.Collections; 
using System.Collections.Generic;
using System.Windows.Media.Animation; 
using System.Windows.Markup; 

namespace System.Windows.Media 
{
    /// 
    /// Collection of Drawing objects
    ///  
    public sealed partial class DrawingCollection : Animatable, IList, IList
    { 
        ///  
        /// Appends the entire input DrawingCollection, while only firing a single set of
        /// public events.  If an exception is thrown from the public events, the 
        /// Append operation is rolled back.
        /// 
        internal void TransactionalAppend(DrawingCollection collectionToAppend)
        { 
            // Use appendCount to avoid inconsistencies & runaway loops when
            // this == collectionToAppend, and to ensure collectionToAppend.Count 
            // is only evaluated once. 
            int appendCount = collectionToAppend.Count;
 
            // First, append the collection
            for(int i = 0; i < appendCount; i++)
            {
                AddWithoutFiringPublicEvents(collectionToAppend.Internal_GetItem(i)); 
            }
 
            // Fire the public Changed event after all the elements have been added. 
            //
            // If an exception is thrown, then the Append operation is rolled-back without 
            // firing additional events.
            try
            {
                FireChanged(); 
            }
            catch (Exception) 
            { 
                // Compute the number of elements that existed before the append
                int beforeAppendCount = Count - appendCount; 

                // Remove the appended elements in reverse order without firing Changed events.

                for (   int i = Count - 1;              // Start at the current last index 
                        i >= beforeAppendCount;         // Until the previous last index
                        i--                             // Move to the preceding index 
                    ) 
                    {
                        RemoveAtWithoutFiringPublicEvents(i); 
                    }

                // Avoid firing WritePostscript events (e.g., OnChanged) after rolling-back
                // the current operation. 
                //
                // This ensures that only a single set of events is fired for both exceptional & 
                // typical cases, and it's likely that firing events would cause another exception. 

                throw; 
            }
        }
    }
} 

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

Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK