Question

I’m really sorry. This must seem like an incredibly stupid question, but unless I ask I’ll never figure it out. I’m trying to write a program to read in a csv file in Visual Basic (tried and gave up on C#) and I asked a friend of mine who is much better at programming than I am. He said I should create a class to hold the data that I read in.

The problem is, I’ve never created a class before, not in VB, Java, or anything. I know all the terms associated with classes, I understand at a high level how classes work no problem. But I suck at the actual details of making one.

So here’s what I did:

Public Class TsvData

    Property fullDataSet() As Array

        Get
            Return ?????
        End Get

        Set(ByVal value As Array)

        End Set

    End Property

End Class

I got as far as the question marks and I’m stuck.
The class is going to hold a lot of data, so I made it an array. That could be a bad move. I don’t know. All i know is that it can’t be a String and it certainly can’t be an Integer or a Float.

As for the Getter and Setter, the reason I put the question marks in is because I want to return the whole array there. The class will eventually have other properties which are basically permutations of the same data, but this is the full set that I will use when I want to save it out or something. Now I want to return the whole Array, but typing “Return fullDataSet()” doesn’t seem like a good idea. I mean, the name of the property is “fullDataSet().” It will just make some kind of loop. But there is no other data to return.

Should I Dim yet another array inside the property, which already is an array, and return that instead?

Answer 1

Usually you use a private member to store the actual data:

Public Class TsvData
Private _fullDataSet As String()
Public Property FullDataSet() As String()
    Get
        Return _fullDataSet
    End Get
    Set(ByVal value As String())
        _fullDataSet = value
    End Set
End Property

Note that this is an instance of bad design since it couples a concept to a concrete representation and allows the clients of the class to modify the internals without any error checking. Returning a ReadOnlyCollection or some dedicated container would be better.