Call function on button click event - vb.net

Question

How do I call this vb.net function on the button click event?
Private Sub GridView_UDGReport_DataBound1(ByVal sender As Object, ByVal e As System.EventArgs) Handles GridView1.DataBound
For rowIndex As Integer = GridView_UDGReport.Rows.Count - 2 To 0 Step -1
Dim gviewRow As GridViewRow = GridView_UDGReport.Rows(rowIndex)
Dim gviewPreviousRow As GridViewRow = GridView_UDGReport.Rows(rowIndex + 1)
For cellCount As Integer = 0 To gviewRow.Cells.Count - 1
If gviewRow.Cells(cellCount).Text = gviewPreviousRow.Cells(cellCount).Text Then
If gviewPreviousRow.Cells(cellCount).RowSpan < 2 Then
gviewRow.Cells(cellCount).RowSpan = 2
Else
gviewRow.Cells(cellCount).RowSpan = gviewPreviousRow.Cells(cellCount).RowSpan + 1
End If
gviewPreviousRow.Cells(cellCount).Visible = False
End If
Next
Next
End Sub

Answer 1

Since you are not using the parameters anyways, you can simply call the method with Nothing as parameter.
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
GridView_UDGReport_DataBound1(Nothing, Nothing)
End Sub

Answer 2

Append the first line so that the sub handles more than one event, as follows:
Private Sub GridView_UDGReport_DataBound1(ByVal sender As Object, ByVal e As System.EventArgs) Handles GridView1.DataBound, Button1.Click
Alternatively, if you need your Click event to run some other code in addition to calling this sub, do this:
Private Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
'do something
GridView_UDGReport_DataBound1(sender, e)
'do something else
End Sub