Each control or component you add in the designer has a field generated for it by default. You can get the value of each field whose type is ContextMenuStrip like so:
vb.net Code:
Imports System.Reflection
Public Class Form1
Private contextMenuStrips As ContextMenuStrip()
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Dim fields = Me.GetType().GetFields(BindingFlags.NonPublic Or
BindingFlags.Instance Or
BindingFlags.DeclaredOnly)
contextMenuStrips = fields.Where(Function(fi) fi.FieldType Is GetType(ContextMenuStrip)).
Select(Function(fi) fi.GetValue(Me)).
Cast(Of ContextMenuStrip)().
ToArray()
End Sub
End Class