Fetching Different Values in LINQ Concurrency Conflict

If you have not read my article Resolving Concurrency conflicts in LINQ then I strongly recommend that you read it first. This article is a simple added extension of the previous article.

After reading resolving concurrency conflict in LINQ you are pretty much aware of mechanisms for concurrency conflict resolution. Now assume a requirement that you need to print or fetch:

1. Current value of an object
2. Original value of an object in the context
3. Current data base value.

This is very much possible by

1. Enumerating over MemberConflicts of ChangeConflict object.
2. Fetching MemberChangeConflict in object of MemberConflict
   
   
   

In child a foreach loop you can fetch values such as:



The Catch statement however should be modified as shown below to fetch and print multiple values.



For reference you can find the full source code below:

using System;
using System.Linq;
using System.Data.Linq;
 
namespace Concurrency
{
    class Program
    {
        static void Main(string[] args)
        {
 
            DataClasses1DataContext context = new DataClasses1DataContext();
 
            #region without handling Conflict
            //Person personToUpdate = (from r in context.Persons
            //                         where r.PersonID == 1
            //                         select r).FirstOrDefault();
            //personToUpdate.FirstName = "John Papa";
            //context.SubmitChanges();
 
            #endregion 
 
            #region hanlding conflict 
 
            try
            {
                Person personToUpdateConflict = (from r in context.Persons
                                                 where r.PersonID == 1
                                                 select r).FirstOrDefault();
                personToUpdateConflict.FirstName = "John";
                context.SubmitChanges(ConflictMode.FailOnFirstConflict);
 
            }
            catch (ChangeConflictException c)
            {
                foreach (ObjectChangeConflict o in context.ChangeConflicts)
                {
                    o.Resolve(RefreshMode.KeepChanges);
 
                    foreach (MemberChangeConflict c1 in o.MemberConflicts)
                    {
                        var currentValue = c1.CurrentValue;
                        var originalValue = c1.OriginalValue;
                        var dataBaseValue = c1.DatabaseValue; 
 
                        Console.WriteLine("Current Value of Object " + c1.CurrentValue);
                        Console.WriteLine("Original value in context " + c1.OriginalValue);
                        Console.WriteLine("Database value " + c1.DatabaseValue);
                    }
                    
                }
                context.SubmitChanges();
 
            }
 
            #endregion 
            Console.ReadKey(true);
        }
    }
}

Upon execution of the application, you should get output as shown below.



I hope this article was useful. Thanks for reading.