倍数。如果在VB.NET

Question

条件请帮我缩短了下面的代码：

If Val(TB.Text) = 0 Then 
    OvalShape1.BackColor = Color.Gray 
ElseIf Val(TB.Text) = 1 Then 
    OvalShape1.BackColor = Color.Lime 
ElseIf Val(TB.Text) = 2 Then 
    OvalShape1.BackColor = Color.Red 
ElseIf Val(TB.Text) = 3 Then 
    OvalShape1.BackColor = Color.White 
End If 

Answer 1

这将做到这一点：

Dim colors As System.Drawing.Color() = {Color.Gray, Color.Lime, Color.Red, Color.White} 

OvalShape1.BackColor = colors(Val(TB.Text)) 

但最好是添加一些验证，支付无效输入TB.Text会导致运行时错误。这里是更长的时间，但更好的代码：

Dim colors As System.Drawing.Color() = {Color.Gray, Color.Lime, Color.Red, Color.White} 
Dim value as Integer 

value = Val(TB.Text) 
If value >= 0 And value <= colors.GetUpperBound(0) Then 
    OvalShape1.BackColor = colors(value) 
End If