宣言されていません。アクセスできない保護レベルになっています。

Question

下のやつの頭文字”ｇ”が宣言されていません。アクセスできない保護レベルになっています。

と表示されてしまいます。どうすればよいですか

Public Class Form1

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

        g.FillRectangle(Brushes.Black, 300, 30, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 50, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 70, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 90, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 110, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 130, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 150, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 170, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 190, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 210, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 230, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 250, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 270, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 290, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 310, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 330, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 350, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 370, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 390, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 410, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 430, 20, 20)
        g.FillRectangle(Brushes.Black, 320, 450, 20, 20)
        g.FillRectangle(Brushes.Black, 300, 470, 20, 20)

        g.FillEllipse(Brushes.Red, 900, 280, 60, 60)

        g.FillRectangle(Brushes.Red, 800, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 800, 140, 100, 60)
        System.Threading.Thread.Sleep(1000)

        g.FillEllipse(Brushes.Yellow, 900, 340, 60, 60)

        System.Threading.Thread.Sleep(1100)

        g.FillEllipse(Brushes.LightGreen, 900, 400, 60, 60)

        System.Threading.Thread.Sleep(1000)
        g.FillRectangle(Brushes.White, 800, 70, 100, 60)
        g.FillRectangle(Brushes.White, 800, 140, 100, 60)
        g.FillRectangle(Brushes.Red, 770, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 770, 140, 100, 60)
        g.FillRectangle(Brushes.White, 900, 280, 60, 60)

        System.Threading.Thread.Sleep(1000)
        g.FillRectangle(Brushes.White, 770, 70, 100, 60)
        g.FillRectangle(Brushes.White, 770, 140, 100, 60)
        g.FillRectangle(Brushes.Red, 735, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 765, 140, 100, 60)
        g.FillEllipse(Brushes.LightGreen, 880, 400, 60, 60)
        g.FillEllipse(Brushes.Yellow, 880, 340, 60, 60)

        g.FillEllipse(Brushes.Red, 880, 280, 60, 60)

        System.Threading.Thread.Sleep(1000)
        g.FillRectangle(Brushes.White, 740, 70, 100, 60)
        g.FillRectangle(Brushes.White, 765, 140, 100, 60)
        g.FillRectangle(Brushes.Red, 730, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 740, 140, 100, 60)

        System.Threading.Thread.Sleep(1000)
        g.FillRectangle(Brushes.White, 730, 70, 100, 60)
        g.FillRectangle(Brushes.White, 740, 140, 100, 60)
        g.FillRectangle(Brushes.Red, 720, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 710, 140, 100, 60)

        System.Threading.Thread.Sleep(1000)
        g.FillRectangle(Brushes.White, 720, 70, 100, 60)
        g.FillRectangle(Brushes.White, 710, 140, 100, 60)
        g.FillRectangle(Brushes.Red, 710, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 660, 140, 100, 60)

        System.Threading.Thread.Sleep(1000)
        g.FillRectangle(Brushes.White, 710, 70, 100, 60)
        g.FillRectangle(Brushes.White, 660, 140, 100, 60)
        g.FillRectangle(Brushes.Red, 670, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 655, 140, 100, 60)

        System.Threading.Thread.Sleep(1000)
        g.FillRectangle(Brushes.White, 670, 70, 100, 60)
        g.FillRectangle(Brushes.White, 655, 140, 100, 60)
        g.FillRectangle(Brushes.Red, 645, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 645, 140, 100, 60)

        System.Threading.Thread.Sleep(1000)
        g.FillRectangle(Brushes.White, 645, 70, 100, 60)
        g.FillRectangle(Brushes.White, 645, 140, 100, 60)
        g.FillRectangle(Brushes.Red, 600, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 635, 140, 100, 60)

        System.Threading.Thread.Sleep(1000)
        g.FillRectangle(Brushes.White, 600, 70, 100, 60)
        g.FillRectangle(Brushes.White, 635, 140, 100, 60)
        g.FillRectangle(Brushes.Red, 580, 70, 100, 60)
        g.FillRectangle(Brushes.Blue, 570, 140, 100, 60)

    End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    End Sub
End Class

Answer 1

g が宣言されていないのでフォームに直接描画を行うには下記のようにしてみてはいかがでしょうか？

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
  Dim g As Graphics
  g = Me.CreateGraphics

'...描画処理（ご質問で書かれているような描画処理）

End Sub

ただ、上記の処理はボタンを押下した際に1度だけ画面に直接描画するだけなので、画面の再描画が必要になっても
自動的に再描画は行ってくれません。再描画については下記の投稿が参考になるかと思います。

https://social.msdn.microsoft.com/Forums/vstudio/ja-JP/3e52f1bd-7c32-4f93-9c30-4c9016ff8468