sql-server - 通过存储过程和 c# 从 SQL Server 返回输出参数

Question

我很难从 SQL Server 获取输出值。

这是我的存储过程:

ALTER PROCEDURE [dbo].[Insert_UnknownCustomer_Quote_Document]
-- Add the parameters for the stored procedure here
@NewDocumentFileName nvarchar(100),
@NewDocumentWordCount int,
@NewQuoteAmount money,
@NewQuoteNumber int OUTPUT = 0

AS

DECLARE @Today datetime
SELECT @Today = GETDATE()

BEGIN TRANSACTION
BEGIN TRY

BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from interfering with SELECT statements.
SET NOCOUNT ON;


-- Insert statements for procedure here
INSERT INTO dbo.Customers(DateAdded)
VALUES (@Today)

INSERT INTO dbo.Quotes(CustomerID, QuoteAmount, QuoteDate)
VALUES (@@IDENTITY, @NewQuoteAmount, @Today)

SELECT @NewQuoteNumber = @@IDENTITY
INSERT INTO dbo.DocumentFiles(QuoteNumber, DocumentFileName, DocumentFileWordCount)
VALUES (@NewQuoteNumber, @NewDocumentFileName, @NewDocumentWordCount)

-- Return quote number
RETURN @NewQuoteNumber

END
COMMIT TRANSACTION
END TRY

BEGIN CATCH
ROLLBACK TRANSACTION
PRINT 'Transaction rolled back.'
END CATCH

这是我的 C#:

SqlParameter returnQuoteNumber = new SqlParameter("@NewQuoteNumber", SqlDbType.Int);
        returnQuoteNumber.Direction = ParameterDirection.ReturnValue;
        newSQLCommand.Parameters.Add(returnQuoteNumber);

这是我现在收到的错误:

Procedure or function 'Insert_UnknownCustomer_Quote_Document' expects parameter '@NewQuoteNumber', which was not supplied.

我试过从开头取出@NewQuoteNumber 并将其放在带有 DECLARE 的 AS 之后，但这也会产生错误。

Answer 1

你想要 ParameterDirection.Output 而不是 ParameterDirection.ReturnValue

也把它从return部分拿出来，return应该用来返回状态而不是值

如果你确实使用 return，我会在事务提交之后而不是之前做