Private Sub DrawLight（ByVal LightToDraw As TrafficLightStatus, _
ByVal grfGraphics As Graphics）

Dim nCircleX As Integer
Dim nCircleY As Integer
Dim nCircleDiameter As Integer
Dim nCircleColor As Color

' 找到所有圆的 X 坐标和直径
nCircleX = CInt（Me.Size.Width * 0.02）
nCircleDiameter = CInt（Me.Size.Width * 0.96）
Select Case LightToDraw
Case TrafficLightStatus.statusRed
If LightToDraw = Me.Status Then
nCircleColor = Color.OrangeRed
Else
nCircleColor = Color.Maroon
End If
nCircleY = CInt（Me.Size.Height * 0.01）
Case TrafficLightStatus.statusYellow
If LightToDraw = Me.Status Then
nCircleColor = Color.Yellow
Else
nCircleColor = Color.Tan
End If
nCircleY = CInt（Me.Size.Height * 0.34）
Case TrafficLightStatus.statusGreen
If LightToDraw = Me.Status Then
nCircleColor = Color.LimeGreen
Else
nCircleColor = Color.ForestGreen
End If
nCircleY = CInt（Me.Size.Height * 0.67）

End Select
Dim bshBrush As System.Drawing.Brush
If LightToDraw = Me.Status Then

bshBrush = New SolidBrush（nCircleColor）
Else
bshBrush = New SolidBrush（Color.FromArgb（60, nCircleColor））
End If

' 绘制代表红绿灯的圆
grfGraphics.FillEllipse（bshBrush, nCircleX, nCircleY, nCircleDiameter, nCircleDiameter）

' 释放笔刷
bshBrush.Dispose（）

End Sub