VB.NET - Object reference not set to an instance of an object
- by Daniel
I need some help with my program. I get this error when I run my VB.NET program with a custom DayView control.
***** Exception Text *******
System.NullReferenceException: Object reference not set to an instance of an object.
at SeaCow.Main.DayView1_ResolveAppointments(Object sender, ResolveAppointmentsEventArgs args) in C:\Users\Daniel\My Programs\Visual Basic\SeaCow\SeaCow\SeaCow\Main.vb:line 120
at Calendar.DayView.OnResolveAppointments(ResolveAppointmentsEventArgs args)
at Calendar.DayView.OnPaint(PaintEventArgs e)
at System.Windows.Forms.Control.PaintWithErrorHandling(PaintEventArgs e, Int16 layer)
at System.Windows.Forms.Control.WmPaint(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
According to the error code, the 'for each' loop below is causing the NullReferenceException error. At default, the 'appointments' list is assigned to nothing and I can't find where the ResolveAppointments function is being called at.
Private Sub DayView1_ResolveAppointments(ByVal sender As Object, ByVal args As Calendar.ResolveAppointmentsEventArgs) Handles DayView1.ResolveAppointments
Dim m_Apps As New List(Of Calendar.Appointment)
For Each m_App As Calendar.Appointment In appointments
If (m_App.StartDate >= args.StartDate) AndAlso (m_App.StartDate <= args.EndDate) Then
m_Apps.Add(m_App)
End If
Next
args.Appointments = m_Apps
End Sub
Anyone have any suggestions?