How do I fire an event in VB.NET code?

I have a form that has a start button (to allow users to run the processes over and over if they wish), and I want to send a btnStart.Click event when the form loads, so that the processes start automatically.

I have the following function for the btnStart.Click event, but how do I actually tell Visual Basic 'Pretend someone has clicked the button and fire this event'?

I've tried going very simple, which essentially works. However, Visual Studio gives me a warning Variable 'sender' is used before it has been assigned a value, so I'm guessing this is not really the way to do it:

Dim sender As Object
btnStart_Click(sender, New EventArgs())

I have also tried using RaiseEvent btnStart.Click, but that gives the following error:

'btnStart' is not an event of 'MyProject.MyFormClass

Code

Imports System.ComponentModel

Partial Public Class frmProgress

    Private bw As BackgroundWorker = New BackgroundWorker

    Public Sub New()

        InitializeComponent()

        ' Set up the BackgroundWorker
        bw.WorkerReportsProgress = True
        bw.WorkerSupportsCancellation = True
        AddHandler bw.DoWork, AddressOf bw_DoWork
        AddHandler bw.ProgressChanged, AddressOf bw_ProgressChanged
        AddHandler bw.RunWorkerCompleted, AddressOf bw_RunWorkerCompleted

        ' Fire the 'btnStart.click' event when the form loads
        Dim sender As Object
        btnStart_Click(sender, New EventArgs())

    End Sub

    Private Sub btnStart_Click(sender As Object, e As EventArgs) Handles btnStart.Click

        If Not bw.IsBusy = True Then

            ' Enable the 'More >>' button on the form, as there will now be details for users to view
            Me.btnMore.Enabled = True

            ' Update the form control settings so that they correctly formatted when the processing starts
            set_form_on_start()

            bw.RunWorkerAsync()

        End If

    End Sub

    ' Other functions exist here

End Class

You should send a button as sender into the event handler:

btnStart_Click(btnStart, New EventArgs())