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Entity Framework 6.0 Tutorials(6):Transaction support

2016-07-07 11:47  追忆似水流年  阅读(246)  评论(0编辑  收藏  举报

Transaction support:

Entity Framework by default wraps Insert, Update or Delete operation in a transaction, whenever you execute SaveChanges(). EF starts a new transaction for each operation and completes the transaction when the operation finishes. When you execute another such operation, a new transaction is started.

EF 6 has introduced database.BeginTransaction and Database.UseTransaction to provide more control over transactions. Now, you can execute multiple operations in a single transaction as shown below:

using (System.Data.Entity.DbContextTransaction dbTran = context.Database.BeginTransaction( ))
{
        try
        {
            Student std1 = new Student() { StudentName = "newstudent" };
            context.Students.Add(std1);
            context.Database.ExecuteSqlCommand(
                @"UPDATE Student SET StudentName = 'Edited Student Name'" +
                    " WHERE StudentID =1"
                );
            context.Students.Remove(std1);

            //saves all above operations within one transaction
            context.SaveChanges();

            //commit transaction
            dbTran.Commit();
        }
        catch (Exception ex)
        {
            //Rollback transaction if exception occurs
            dbTran.Rollback();
        }

}

 

database.UseTransaction allows the DbContext to use a transaction which was started outside of the Entity Framework.

Download DB First sample project for Transactions demo.