我如何获得SQL Server存储过程在c＃中的返回值？

Question

我在C＃和SQL Server初学者，我写了这个查询创建SQL Server中的存储过程：

create procedure newBehzad 
    @id bigint 
as 
    DECLARE @ResultValue int 

    select * 
    from TABLEA 
    where id > @id 

    SET @ResultValue = -5 
go 

一切工作，和我写了这个C＃代码来调用存储过程，它返回一个值：

using (var conn = new SqlConnection(connectionString)) 
using (var command = new SqlCommand("newBehzad", conn) 
{ 
    CommandType = CommandType.StoredProcedure 
}) 
{ 
    conn.Open(); 

    command.Parameters.Add("@id", SqlDbType.BigInt).Value = 2; 
    command.Parameters.Add("@ResultValue", SqlDbType.Int); 

    SqlParameter retval = command.Parameters.Add("@ResultValue", SqlDbType.Int); 
    retval.Direction = ParameterDirection.ReturnValue; 

    retunvalue = (string)command.Parameters["@ResultValue"].Value; 

    //SqlParameter retval = sqlcomm.Parameters.Add("@b", SqlDbType.VarChar); 
    command.ExecuteNonQuery(); 
    conn.Close(); 
} 

MessageBox.Show(returnValue); 

但是当我运行的C＃Windows应用程序，我得到这个错误：

Procedure or function newBehzad has too many arguments specified.

我该如何解决呢？谢谢。

Answer 1

改变你程序进行：

create procedure newBehzad @id bigint, @ResultValue int OUT 
as 
SET @ResultValue = 0 
BEGIN 
    select *from TABLEA 
    where id>@id 
    SET @ResultValue = -5 
END 
go 

请尝试somethink这样的：

object returnValue = null; 
      using (var conn = new System.Data.SqlClient.SqlConnection(AbaseDB.DBFactory.GetInstance().GetConnectionString())) 
      { 
       using (System.Data.SqlClient.SqlCommand command = new System.Data.SqlClient.SqlCommand("newBehzad", conn) { CommandType = CommandType.StoredProcedure }) 
       { 
        conn.Open(); 
        command.Parameters.Add("@id", SqlDbType.BigInt).Value = 2; 
        command.Parameters.Add("@ResultValue", SqlDbType.Int).Direction = ParameterDirection.Output; 

        command.ExecuteNonQuery(); 

        returnValue = command.Parameters["@ResultValue"].Value; 

        conn.Close(); 
       } 
       if (returnValue != null) 
        MessageBox.Show(returnValue.ToString()); 
      } 

Answer 2

using (var conn = new SqlConnection(connectionString)) 
      using (var command = new SqlCommand("newBehzad", conn) 
      { 
       CommandType = CommandType.StoredProcedure 
      }) 
      { 
       conn.Open(); 
       command.Parameters.Add("@id", SqlDbType.BigInt).Value = 2; 
       // command.Parameters.Add("@ResultValue", SqlDbType.Int); Comment this line 


       SqlParameter retval = command.Parameters.Add("@ResultValue", SqlDbType.Int); 
       retval.Direction = ParameterDirection.ReturnValue; 

       retunvalue = (string)command.Parameters["@ResultValue"].Value; 

       //SqlParameter retval = sqlcomm.Parameters.Add("@b", SqlDbType.VarChar); 
       command.ExecuteNonQuery(); 
       conn.Close(); 
      } 
      MessageBox.Show(returnValue); 

Answer 3

所有你需要改变存储过程返回值首先：

create procedure newBehzad @id bigint 
as 
    DECLARE @ResultValue int 
    select *from TABLEA 
    where id>@id 
    SET @ResultValue = -5 

    Return @ResultValue 
go 

然后抓住它：

using (var conn = new SqlConnection(connectionString)) 
{ 
    conn.Open();   

    using (var cmd = new SqlCommand("newBehzad", conn) 
    { 
     cmd.CommandType = CommandType.StoredProcedure; 

     SqlParameter retval = new SqlParameter(); 
     retval.Direction = ParameterDirection.ReturnValue; 

     cmd.Parameters.Add("@id", SqlDbType.BigInt).Value = 2; 
     cmd.Parameters.Add(retval); 

     cmd.ExecuteNonQuery(); 

     returnValue = (int)retval.Value; 
    } 
} 

但我真的不能让你为什么在存储过程中选择数据...