无法使用实体框架读取从存储过程返回的值

Question

我编写了一个存储过程，如果找到，它将返回一行的 ID，如果没有找到，将创建一行并返回新创建的行的 ID。我在 C# 函数中检索此返回值时遇到问题。

---

存储过程：

PROCEDURE [TagDatabase].[GetTagID] 
    -- Add the parameters for the stored procedure here
    @TagName as varchar(200), 
    @UserID int = 0,
    @TagID int = 0 OUTPUT
AS
BEGIN
    -- SET NOCOUNT ON added to prevent extra result sets from
    -- interfering with SELECT statements.
    SET NOCOUNT ON;
    select @TagID=ID from Tag where Name = @TagName and UserID=@UserID;
    IF NULLIF(@TagID, '') IS NULL
    BEGIN
        DECLARE @OutputTbl TABLE (ID INT)

        INSERT INTO Tag(Name, ParentID, UserID)
        OUTPUT INSERTED.ID INTO @OutputTbl(ID)
        VALUES (@TagName, 0, @UserID);

        select @TagID=ID from @OutputTbl


    END

    select @TagID
END

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我的函数来检索 this 返回的值：

ObjectParameter objParam = new ObjectParameter("TagID", typeof(long));

context.GetTagID("newTag", 10, objParam);
context.SaveChanges();
long id = Convert.ToInt64(Convert.ToInt64(id)));

Answer 1

改变

long id = Convert.ToInt64(Convert.ToInt64(id)));

到

long id = Convert.ToInt64(objParam.Value);