Return an output parameter from SQL Server via a stored procedure and c#

Question

I am having a devil of a time getting an output value from SQL Server.

Here is my stored procedure:

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

And here is my C#:

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

Here is the error I am receiving now:

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

I have tried taking @NewQuoteNumber out of the beginning and placing it after the AS with a DECLARE but that produces an error, too.

Solution 1

you want ParameterDirection.Output not ParameterDirection.ReturnValue

Also take it out of the return part, return should be used to return a status not a value

And if you do use return, I would do it after the transaction is committed not before

Solution 2

SqlCommand.Parameters.Add("@NewQuoteNumber", SqlDbType.Int).Direction = ParameterDirection .Output ;

<SqlCommand>.ExecuteNonQuery();

int NewQuoteNumber = int.Parse(SqlCommand.Parameters["@NewQuoteNumber"].Value .ToString ());

now you can use this value into your code .