Getting return value from stored procedure in ADO.NET

Question

I know that there is another question with nearly the same title, but it doesn\'t answer my question. I have a stored procedure, which returns the unique identifier after in

Answer 1

Just tried on my box and this works for me:

In SQL Server:

DROP PROCEDURE TestProc;
GO
CREATE PROCEDURE TestProc
AS
   RETURN 123;
GO

In C#

        string cnStr = "Server=.;Database=Sandbox;Integrated Security=sspi;";
        using (SqlConnection cn = new SqlConnection(cnStr)) {
            cn.Open();
            using (SqlCommand cmd = new SqlCommand("TestProc", cn)) {
                cmd.CommandType = CommandType.StoredProcedure;
                SqlParameter returnValue = new SqlParameter();
                returnValue.Direction = ParameterDirection.ReturnValue;
                cmd.Parameters.Add(returnValue);

                cmd.ExecuteNonQuery();
                Assert.AreEqual(123, (int)returnValue.Value);
            }
        }

Answer 2

Some one can also use this simple and short method to calculate return value from SP

In SQL:

Create Table TestTable 
(
 Int Id
)

CREATE PROCEDURE Proc_TestProc
 @Id
 AS
   Begin
     Set NOCOUNT ON  //Use this line if you don't want to return any message from SQL

     Delete from TestTable where Id = @Id
     return 1

     Set NOCOUNT OFF //NOCOUNT OFF is Optional for NOCOUNT ON property
   End

Sql Server always returns Int type value only.

and in C#

using (SqlConnection conn = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["TestConnectionString"].ToString()))
using (SqlCommand cmd = new SqlCommand("Proc_TestProc", conn))
{
 cmd.CommandType = CommandType.StoredProcedure;

 cmd.Parameters.AddWithValue("@Id", 1);
 var returnParameter = cmd.Parameters.Add("@ReturnVal", SqlDbType.Int);
 returnParameter.Direction = ParameterDirection.ReturnValue;

 conn.Open();
 cmd.ExecuteNonQuery();
 var result = returnParameter.Value;
}

You can also check your return value in SQL by using this command:

DECLARE @return_status int;
EXEC @return_status = dbo.[Proc_TestProc] 1;
SELECT 'Return Status' = @return_status;
print 'Returned value from Procedure: ' + Convert(varchar, @return_status); // Either previous or this line both will show you the value of returned value

Answer 3

you can use standart ways that you use before in normal queries but in Sql command you must write EXEC before your store procedure name and dont use commandtype like this :

 SqlConnection con = new SqlConnection(["ConnectionString"])
    SqlCommand com = new SqlCommand("EXEC _Proc @id",con);
    com.Parameters.AddWithValue("@id",["IDVALUE"]);
    con.Open();
    SqlDataReader rdr = com.ExecuteReader();
    ArrayList liste = new ArrayList();
    While(rdr.Read())
    {
    liste.Add(rdr[0]); //if it returns multiple you can add them another arrays=> liste1.Add(rdr[1]) ..
    }
    con.Close();

Answer 4

Do you get the value of you EXEC in TSQL? I wonder if refactoring the TSQL would help (and using SCOPE_IDENTITY():

so change:

COMMIT TRAN T1
RETURN @@IDENTITY

to:

SET @auctionID = SCOPE_IDENTITY()
COMMIT TRAN T1
RETURN @auctionID

(I would also change the other @@IDENTITY to SCOPE_IDENTITY())

---

As a minor optimisation, you could also use:

return (int)retval.Value;

but this side of things should have worked "as is" from what I can see (hence why I'm focusing on the TSQL).

Answer 5

I solved the problem: you have to set SqlCommand.CommandType to CommandType.StoredProcedure in order to get return values and/or output parameters. I haven't found any documentation about that, but now everything works.