vb Code:
  1. Private Sub treeview1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles treeview1.MouseDown
  2.         If e.Button = Windows.Forms.MouseButtons.Right Then
  3.             treeview1.SelectedNode = treeview1.GetNodeAt(e.X, e.Y)
  4.         End If
  5.     End Sub