How can I call a sqlserver function from VB.net(or C#) ? Is there some syntax like stored procedure?

Question

Public Sub cleanTables(ByVal prOKDel As Short)
     Dim sqlParams(1) As SqlParameter
     Dim sqlProcName As String
     sqlProcName = "db.dbo.sp_mySP"
     sqlParams(1) = New SqlParameter("@OKDel", prOKDel)
     Try
         dbConn.SetCommandTimeOut(0)
         dbConn.ExecuteNonQuery(CommandType.StoredProcedure, sqlProcName, sqlParams)
     Catch ex As Exception

     Finally

     End Try
End Sub

Is there

 CommandType.StoredProcedure...CommandType.Function
sqlParams(1) = New SqlParameter("@OKDel", prOKDel)...

and finally datatable dt = dbConn.Execute(CommandType.StoredProcedure, sqlProcName, sqlParams)

Thanks

Solution 1

Sorry, there is no way to run a function directly. Either call it using a sql Text command

Public Sub RunFunction(ByVal input As Short)
            Using myConnection As New Data.SqlClient.SqlConnection
                Using myCommand As New Data.SqlClient.SqlCommand("Select dbo.MyFunction(@MyParam)", myConnection)
                    myCommand.CommandType = CommandType.Text
                    myCommand.Parameters.Add(New Data.SqlClient.SqlParameter("@MyParam", input))
                    myCommand.CommandTimeout = 0
                    Try
                        myCommand.ExecuteNonQuery()
                    Catch ex As Exception

                    End Try
                End Using

            End Using
        End Sub

Or Wrap a procedure round it...

Create Procedure RunMyFunction(@MyParam as int)
Select * FROM dbo.MyFunction(@MyParam)
Go

Solution 2

Yes you can call a function directly as demonstrated below.

Dim dtaName As New SqlClient.SqlDataAdapter

dtaName.SelectCommand = New SqlClient.SqlCommand
With dtaName.SelectCommand
    .CommandTimeout = 60
    .Connection = prvcmpINC.cntINC
    .CommandType = CommandType.StoredProcedure
    .CommandText = "dbo.app_GetName"
    .Parameters.AddWithValue("@ParamToPassIn", parstrParamToPassIn)
    .Parameters.Add("@intResult", SqlDbType.Int)
    .Parameters("@intResult").Direction = ParameterDirection.ReturnValue
End With

dtaName.SelectCommand.ExecuteScalar()
intRuleNo = dtaName.SelectCommand.Parameters("@intResult").Value

Solution 3

This works for me and is based on one of the above answers using a SqlDataAdapter (note that you do not need to use one) and ExecuteScalar (can use ExecuteNonQuery as shown here):

bool res = false;
using (SqlConnection conn = new SqlConnection(GetConnectionString()))
{
    using (SqlCommand comm = new SqlCommand("dbo.MyFunction", conn))
    {
        comm.CommandType = CommandType.StoredProcedure;

        SqlParameter p1 = new SqlParameter("@MyParam", SqlDbType.Int);
        // You can call the return value parameter anything, .e.g. "@Result".
        SqlParameter p2 = new SqlParameter("@Result", SqlDbType.Bit);

        p1.Direction = ParameterDirection.Input;
        p2.Direction = ParameterDirection.ReturnValue;

        p1.Value = myParamVal;

        comm.Parameters.Add(p1);
        comm.Parameters.Add(p2);

        conn.Open();
        comm.ExecuteNonQuery();

        if (p2.Value != DBNull.Value)
            res = (bool)p2.Value;
    }
}
return res;