VB.Net Member Field

In VB.Net you can set the visibility of a member field to any visibility: private, protected, public, friend or protected friend.

You can intialize a member field with a default when declared. If you set the member field value in your constructor, it will override the default value.

Finally, you can use the Shared modifier (no instance required) and ReadOnly modifier (similar to a constant).

A Simple Example

The following example uses our class above. Notice for the static member, we do not use a variable, instead we use the class name directly. That's why static members are sometimes referred to as class members. Static members belong to the class and are referenced by the class name.

Note: The public member fields CyborgName and CyborgAge are used here for demonstration only. You normally want to make them private and access them via a member property.

Public Class Form1

  Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click 

    'Read static member field BEFORE we create our object.
    'Notice the use of the class name, not an object name.
    MessageBox.Show("We will now build a series " & Cyborg.SeriesID & " robot.")

    Dim MyRobot As New Cyborg

    MyRobot.CyborgName = "John"
    MyRobot.CyborgAge = 34

    MessageBox.Show("We created a " & MyRobot.CyborgAge & " year old robot named " & MyRobot.CyborgName & ".")

    'You should not refer to static members using an instance.
    'You will get a compiler warning (in C# you get a compiler error).
    'MessageBox.Show("A series " & MyRobot.SeriesID & " robot.")

    'Use a type name instead.
    MessageBox.Show("A series " & Cyborg.SeriesID & " robot.")

  End Sub
End Class

 
Public Class Cyborg
  Private FSerialNumber As String = "A100"

  Public CyborgName As String

  Public CyborgAge As Integer

  Public Shared ReadOnly SeriesID As Integer = 100
End Class