Oop

[SLG29]

Can anyone help with an OOP problem I've got

This is my first crack at OOP and I've got to produce a payroll program consisting of an abstract base class employee and 4 derived classes, the base class includes an abstract readonly property called monthlypay

There are 2 buttons on the form clicking create instantiates the object and clicking display shows the information in a messagebox which has just been inputted in the textboxes this is firstname, lastname and monthlypay

This is what I have so far for creating say for example a new boss class object which is one of the derived classes

Boss class code

Public Overrides Function ToString() As String
Return "boss: " (this has to be in the form "boss: John Doe")
End Function

Public Overrides ReadOnly Property MonthlyPay() As String
Get
Return annualsalary /12
End Get
End Property

Create button code

Dim boss as New cboss(firstname, lastname, annualsalary)

Display button code
Dim boss as New cboss(firstname, lastname, annualsalary)
firstname = textbox1.text
lastname = textbox2.text
Dim strMessage As String
strMessage = boss.monthlypay & firstname & lastname

Problem I have is I can't display the info in the messagebox, does anyone know how the ToString and ReadOnly properties should be incorporated in the messagebox

Thanks