Visual Basic .NET Language NullReferenceException Uninitialized variable
Example
BAD CODE
Dim f As System.Windows.Forms.Form
f.ShowModal()
GOOD CODE
Dim f As System.Windows.Forms.Form = New System.Windows.Forms.Form
' Dim f As New System.Windows.Forms.Form ' alternative syntax
f.ShowModal()
EVEN BETTER CODE (Ensure proper disposal of IDisposable object more info)
Using f As System.Windows.Forms.Form = New System.Windows.Forms.Form
' Using f As New System.Windows.Forms.Form ' alternative syntax
f.ShowModal()
End Using
