Let's suppose we want a program that will count the number of times you click a button.
The code shown below will not work because the value of counter is reset to 0 each time the function executes.
Public Class Form1
Private Sub BtnCounter_Click(sender As Object, e As EventArgs) Handles BtnCounter.Click
Dim counter As Integer = 0
counter += 1
Me.Text = counter
End Sub
End Class
Instead, we need to declare the variable as static so that the value is maintained throughout the execvution of the program:
Public Class Form1
Private Sub BtnCounter_Click(sender As Object, e As EventArgs) Handles BtnCounter.Click
Static counter As Integer = 0
counter += 1
Me.Text = counter
End Sub
End Class