公司舉辦年會要做個Bingo抽獎遊戲，請我開發這個Bingo程式。

現功能已按要求做好。其中的隨機出號效果用了幾個由小到大的 Label 來簡單實現。主要VB.NET 程式碼如下：

            hitIndex = rand.Next(0, numRemainList.Count - 1)
            hitNum = numRemainList.Item(hitIndex)

            LabelD1.Text = hitNum
            LabelD2.Text = hitNum
            LabelD3.Text = hitNum
            LabelD4.Text = hitNum

            LabelD1.Visible = True
            LabelD2.Visible = False
            LabelD3.Visible = False
            LabelD4.Visible = False
            Me.Refresh()
            System.Threading.Thread.Sleep(200)

            LabelD1.Visible = False
            LabelD2.Visible = True
            Me.Refresh()
            System.Threading.Thread.Sleep(300)

            LabelD2.Visible = False
            LabelD3.Visible = True
            Me.Refresh()
            System.Threading.Thread.Sleep(500)

            LabelD3.Visible = False
            LabelD4.Visible = True
            Me.Refresh()
            System.Threading.Thread.Sleep(1000)

            LabelD4.Visible = False
            Me.Refresh()

            RichTextBoxSelected.Text &= hitNum & "   "
            Me.Refresh()