EF事务

EF的SaveChanges默认会开启事务，如果想手动使用事务的话，参考代码如下：

using (var context = new BloggingContext())
{
    using (var transaction = context.Database.BeginTransaction())
    {
        try
        {
            context.Blogs.Add(new Blog { Url = "www.tnblog.net" });
            context.SaveChanges();

            context.Blogs.Add(new Blog { Url = "m.tnblog.net" });
            context.SaveChanges();

            var blogs = context.Blogs
                .OrderBy(b => b.Url)
                .ToList();

            // Commit transaction if all commands succeed, transaction will auto-rollback
            // when disposed if either commands fails
            transaction.Commit();
        }
        catch (Exception)
        {
            // TODO: Handle failure
        }
    }
}