如何获取存储过程返回值

CREATE PROCEDURE [dbo].[nb_order_insert](
@o_buyerid int ,
@o_id bigint OUTPUT
)
AS
BEGIN
SET NOCOUNT ON;
BEGIN
INSERT INTO [Order](o_buyerid )
VALUES (@o_buyerid )
SET @o_id = @@IDENTITY
END
END

		

DECLARE @o_buyerid int
DECLARE @o_id bigint
EXEC [nb_order_insert] @o_buyerid,@o_id output

		

CREATE PROCEDURE [dbo].[nb_order_insert](
@o_buyerid int ,
@o_id bigint OUTPUT
)
AS
BEGIN
SET NOCOUNT ON;
IF(EXISTS(SELECT * FROM [Shop] WHERE [s_id] = @o_buyerid ))
BEGIN
INSERT INTO [Order](o_buyerid ) VALUES (@o_buyerid ) 
SET @o_id = @@IDENTITY 
RETURN 1 — 插入成功返回1 
END 
ELSE 
RETURN 0 — 插入失败返回0 END

		

DECLARE @o_buyerid int
DECLARE @o_id bigint
DECLARE @result bit
EXEC @result = [nb_order_insert] @o_buyerid ,o_id output

		

alter procedure NorthwindSearch
(
     @productID int
)
as
 
return 1
 
go

		

protected void btnBack_Click(object sender, EventArgs e)
...{
        //调用存储过程
        stringconStr=ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ToString();
        SqlConnection conn = new SqlConnection(conStr);
        SqlCommand cmd = new SqlCommand();
        cmd.CommandText = "NorthwindSearch";
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.Connection=conn;
        conn.Open();
        SqlParameter sp = new SqlParameter("@productID", SqlDbType.Int);
        sp.Value = int.Parse(txtProduct.Text.Trim());
        cmd.Parameters.Add(sp);
 
        //定义输出参数
        SqlParameter returnValue = new SqlParameter("@returnValue", SqlDbType.Int);
        returnValue.Direction = ParameterDirection.ReturnValue;
        cmd.Parameters.Add(returnValue);
        cmd.ExecuteNonQuery();
        txtSupplierID.Text = returnValue.Value.ToString();
        conn.Close();
 
}

		

alter procedure NorthwindSearch
(
     @productID int,
     @outputValue nvarchar(50) output
 
)
as
 Select @outputValue=SupplierID 
 from products where ProductID=@productID
go

		

protected void btnBack_Click(object sender, EventArgs e)
...{
        //调用存储过程
        string conStr = System.Configuration.ConfigurationManager.ConnectionStrings["NorthwindConnectionString"].ToString();
        SqlConnection conn = new SqlConnection(conStr);
        SqlCommand cmd = new SqlCommand();
        cmd.CommandText = "NorthwindSearch";
        cmd.CommandType = CommandType.StoredProcedure;
        cmd.Connection=conn;
        conn.Open();
        SqlParameter sp = new SqlParameter("@productID", SqlDbType.Int);
        sp.Value = int.Parse(txtProduct.Text.Trim());
        cmd.Parameters.Add(sp);
 
        //定义输出参数
        sp = new SqlParameter("@outputValue", SqlDbType.NVarChar,50);
        sp.Direction = ParameterDirection.Output;
        cmd.Parameters.Add(sp);
        cmd.ExecuteNonQuery();
        txtSupplierID.Text = cmd.Parameters[1].Value.ToString();
        conn.Close();
 
    }