รบกวนช่วยอธิบาย Code vb.net หน่อยครับ คือผมจะใช้ในการสร้างเกมส์คล้าย Minesweeper ที่มากับวินโดวส์

Private Sub btnNew_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnNew.Click
        Dim I As Integer
        Dim J As Integer    
        btnNew.Enabled = False
        btnExit.Text = " "
        Remaining = 4
        Tries = 0
        lblMugwumps.Text = "4" 
        lblGuesses.Text = "0"         
        MyMap.Clear(pnlGrid.BackColor)
        For I = 0 To 9
            For J = 0 To 9
                Map(I, J) = 0
            Next J
        Next I
        For I = 1 To 4
            Do
                For J = 1 To 2
                    P(I, J) = Int(10 * Rnd())
                Next J
            Loop Until Map(P(I, 1), P(I, 2)) = 0
            Map(P(I, 1), P(I, 2)) = 1
        Next I
        For I = 1 To 4
            Map(P(I, 1), P(I, 2)) = 0
        Next I
        pnlGrid_Paint(Nothing, Nothing)
        lblMessage.Text = " "
        lblMessage.Refresh()
    End Sub