Entity framework 实体框架，AsNoTracking和MergeOption=NoTracking之间的区别是什么？

两者之间的区别是什么

myenties.AsNoTracking（）

和

context.myenties.MergeOption=MergeOption.NoTracking？

我从第二次推荐中选择了合并选项，但我还没有真正找到它。我怀疑“MergeOption”的东西从那时起就被微软删除了。
AsNoTracking只是MergeOption.NoTracking ObjectContext/ObjectSet版本（ef4及以下）的DbContext/DbSet版本（ef4.1以上）

AsNoTracking实现：

public static IQueryable AsNoTracking(this IQueryable source)
        {
            Check.NotNull(source, "source");

            var asDbQuery = source as DbQuery;
            return asDbQuery != null ? asDbQuery.AsNoTracking() : CommonAsNoTracking(source);
        }

private static T CommonAsNoTracking<T>(T source) where T : class
        {
            DebugCheck.NotNull(source);

            var asObjectQuery = source as ObjectQuery;
            if (asObjectQuery != null)
            {
                return (T)DbHelpers.CreateNoTrackingQuery(asObjectQuery);
            }

            var noTrackingMethod = source.GetType().GetPublicInstanceMethod("AsNoTracking");
            if (noTrackingMethod != null
                && typeof(T).IsAssignableFrom(noTrackingMethod.ReturnType))
            {
                return (T)noTrackingMethod.Invoke(source, null);
            }

            return source;
        }

public static IQueryable CreateNoTrackingQuery(ObjectQuery query)
        {
            DebugCheck.NotNull(query);

            var asIQueryable = (IQueryable)query;
            var newQuery = (ObjectQuery)asIQueryable.Provider.CreateQuery(asIQueryable.Expression);
            newQuery.ExecutionStrategy = query.ExecutionStrategy;
            newQuery.MergeOption = MergeOption.NoTracking;
            newQuery.Streaming = query.Streaming;
            return newQuery;
        }

CommonAsNoTracking实现：

public static IQueryable AsNoTracking(this IQueryable source)
        {
            Check.NotNull(source, "source");

            var asDbQuery = source as DbQuery;
            return asDbQuery != null ? asDbQuery.AsNoTracking() : CommonAsNoTracking(source);
        }

private static T CommonAsNoTracking<T>(T source) where T : class
        {
            DebugCheck.NotNull(source);

            var asObjectQuery = source as ObjectQuery;
            if (asObjectQuery != null)
            {
                return (T)DbHelpers.CreateNoTrackingQuery(asObjectQuery);
            }

            var noTrackingMethod = source.GetType().GetPublicInstanceMethod("AsNoTracking");
            if (noTrackingMethod != null
                && typeof(T).IsAssignableFrom(noTrackingMethod.ReturnType))
            {
                return (T)noTrackingMethod.Invoke(source, null);
            }

            return source;
        }

public static IQueryable CreateNoTrackingQuery(ObjectQuery query)
        {
            DebugCheck.NotNull(query);

            var asIQueryable = (IQueryable)query;
            var newQuery = (ObjectQuery)asIQueryable.Provider.CreateQuery(asIQueryable.Expression);
            newQuery.ExecutionStrategy = query.ExecutionStrategy;
            newQuery.MergeOption = MergeOption.NoTracking;
            newQuery.Streaming = query.Streaming;
            return newQuery;
        }

取自
AsNoTracking只是MergeOption.NoTracking ObjectContext/ObjectSet版本（EF 4及以下）的DbContext/DbSet版本（EF 4.1及以上）

AsNoTracking实现：

public static IQueryable AsNoTracking(this IQueryable source)
        {
            Check.NotNull(source, "source");

            var asDbQuery = source as DbQuery;
            return asDbQuery != null ? asDbQuery.AsNoTracking() : CommonAsNoTracking(source);
        }

private static T CommonAsNoTracking<T>(T source) where T : class
        {
            DebugCheck.NotNull(source);

            var asObjectQuery = source as ObjectQuery;
            if (asObjectQuery != null)
            {
                return (T)DbHelpers.CreateNoTrackingQuery(asObjectQuery);
            }

            var noTrackingMethod = source.GetType().GetPublicInstanceMethod("AsNoTracking");
            if (noTrackingMethod != null
                && typeof(T).IsAssignableFrom(noTrackingMethod.ReturnType))
            {
                return (T)noTrackingMethod.Invoke(source, null);
            }

            return source;
        }

public static IQueryable CreateNoTrackingQuery(ObjectQuery query)
        {
            DebugCheck.NotNull(query);

            var asIQueryable = (IQueryable)query;
            var newQuery = (ObjectQuery)asIQueryable.Provider.CreateQuery(asIQueryable.Expression);
            newQuery.ExecutionStrategy = query.ExecutionStrategy;
            newQuery.MergeOption = MergeOption.NoTracking;
            newQuery.Streaming = query.Streaming;
            return newQuery;
        }

CommonAsNoTracking实现：

public static IQueryable AsNoTracking(this IQueryable source)
        {
            Check.NotNull(source, "source");

            var asDbQuery = source as DbQuery;
            return asDbQuery != null ? asDbQuery.AsNoTracking() : CommonAsNoTracking(source);
        }

private static T CommonAsNoTracking<T>(T source) where T : class
        {
            DebugCheck.NotNull(source);

            var asObjectQuery = source as ObjectQuery;
            if (asObjectQuery != null)
            {
                return (T)DbHelpers.CreateNoTrackingQuery(asObjectQuery);
            }

            var noTrackingMethod = source.GetType().GetPublicInstanceMethod("AsNoTracking");
            if (noTrackingMethod != null
                && typeof(T).IsAssignableFrom(noTrackingMethod.ReturnType))
            {
                return (T)noTrackingMethod.Invoke(source, null);
            }

            return source;
        }

public static IQueryable CreateNoTrackingQuery(ObjectQuery query)
        {
            DebugCheck.NotNull(query);

            var asIQueryable = (IQueryable)query;
            var newQuery = (ObjectQuery)asIQueryable.Provider.CreateQuery(asIQueryable.Expression);
            newQuery.ExecutionStrategy = query.ExecutionStrategy;
            newQuery.MergeOption = MergeOption.NoTracking;
            newQuery.Streaming = query.Streaming;
            return newQuery;
        }

摘自
您使用的EntityFramework的哪个版本？合并选项用于ObjectSet/ObjectContext。从4.1开始，DbContext位于ObjectContext之上，并且存在AsNoTracking。@thudbutt我使用6.1.3，所以我的猜测是正确的。它们是一样的吗？是的，在封面下，AsNoTracking使用MergeOption.NoTracking。将在我的回答中添加详细信息。您使用的EntityFramework版本是什么？合并选项用于ObjectSet/ObjectContext。从4.1开始，DbContext位于ObjectContext之上，并且存在AsNoTracking。@thudbutt我使用6.1.3，所以我的猜测是正确的。它们是一样的吗？是的，在封面下，AsNoTracking使用MergeOption.NoTracking。我将在我的回答中添加细节。