Question

I’m attempting to make a generic query executer function. I want to be able to send it a query string and have it return a two-dimensional array containing the results. Below is my code for how to do it with a (9,x) array. How can I do it with an (y,x) sized array? Also, I feel like there must be a more efficient way to do this…

   Dim right As Integer = 0
    dbConn = New SqlConnection("hidden for security purposes")
    MyCommand = New SqlCommand(queryString, dbConn)
    dbConn.Open()
    Dim resultArray(9, 0) As String
    MyDataReader = MyCommand.ExecuteReader()

    While (MyDataReader.Read())
        For i = 0 To 9
            If IsDBNull(MyDataReader(i)) Then
                'resultArray(i, UBound(resultArray, 2)) = ""
            Else
                resultArray(i, UBound(resultArray, 2)) = MyDataReader(i)

            End If
        Next

        ReDim Preserve resultArray(9, UBound(resultArray, 2) + 1)
    End While
    ReDim Preserve resultArray(9, UBound(resultArray, 2) - 1)
    MyDataReader.Close()
    dbConn.Close()

Return resultArray

Answer 1

Try something like this:

Public Function GetData(ByVal queryString As String, ByVal addParameters As Action(Of SqlParameterCollection) As DataTable
    Dim result As New DataTable()
    Using cn As New SqlConnection(" connection string "), _
          cmd As New SqlCommand(queryString, cn)

       addParameters(cmd.Parameters)

       cn.Open()
       Using rdr As SqlCommand.ExecuteReader()
          result.Load(rdr)
       End Using
   End Using
   Return result
End Function

For a query with no parameters, call it like this:

Dim result = GetData("Select * from Table", Sub(p) Exit Sub)

Or if you do have a parameter:

Dim result = GetData("Select * from Table Where ID= @ID", _
    Sub(p)
        p.Add("@ID", SqlDbType.Int).Value = 12345
    End Sub)