sql - 从输出参数 C# 中获取值

Question

嗨，我正在尝试使用输出值在 sql 中创建 sp
这是代码

ALTER PROCEDURE [dbo].[usp_SelectHospital_IfExiste_Department]
@HospitalDepartmentID INT,
@IfExiste INT OUTPUT 
AS

    SET NOCOUNT ON
SET TRANSACTION ISOLATION LEVEL READ COMMITTED
IF NOT EXISTS  (SELECT c.DeptID FROM Clinic c WHERE DeptID=@HospitalDepartmentID )
BEGIN


    SET @IfExiste=0

SELECT
    [HospitalDepartmentID],
    [NAME]
FROM
    [dbo].[Hospital_Department]
WHERE
    [HospitalDepartmentID] = @HospitalDepartmentID

END

ELSE
BEGIN
    SET @IfExiste=1

SELECT
    [HospitalDepartmentID],
    [NAME]
FROM
    [dbo].[Hospital_Department]
WHERE
    [HospitalDepartmentID] = @HospitalDepartmentID
    END

和 C# 代码

public static Hospital_Department GetDepartmentInfo(int ID,int OutIfExist)
        {
            SqlCommand cmd;
            SqlDataReader dr;
            Hospital_Department HD = new Hospital_Department();
            using (cmd = new SqlCommand("usp_SelectHospital_IfExiste_Department", ProjectCon.GetCon()))
            {
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.AddWithValue("@HospitalDepartmentID", ID);
                //cmd.Parameters.Add("@IfExiste",SqlDbType.Int).Direction = ParameterDirection.Output;
                cmd.Parameters.Add("@IfExiste",SqlDbType.Int);
                cmd.Parameters["@IfExiste"].Direction = ParameterDirection.Output;
                dr = cmd.ExecuteReader();
                while (dr.Read())
                {
                    HD.NAME = dr["NAME"].ToString();
                    HD.HospitalDepartmentID = Convert.ToInt32(dr["HospitalDepartmentID"]);
                }
                OutIfExist = Convert.ToInt32(cmd.Parameters["@IfExiste"].Value);
                return HD;
            }

        }

当我尝试获取输出值始终为null并且我在sql中运行存储过程时运行并返回值所以请告诉我我的代码有什么问题thx

Answer 1

也许这个问题有有用的信息：

根据http://msdn.microsoft.com/en-us/library/ms971497，您必须在处理输出参数之前关闭数据读取器。

希望能帮助到你。