海，我有我的代码probleam，我目前有函数sin，COS谭建立科学的计算器。我创建它的代码不能正常工作，因为我每次转换功能，它会显示0 answer.Please建议我如何纠正我的代码在这里。

Public Class Form1

    Dim total1, total2 As Double

    Dim [Operator] As String

    Const conversionFactor As Double = Math.PI / 180

Dim result As Double

        total2 = Val(answer.Text)

 

        Select Case [Operator]

             Case "SIN"

                result = Math.Sin(total1 / conversionFactor)

                answer.Text = result

            Case "COS"

                result = Math.Cos(total1 / conversionFactor)

                answer.Text = result

            Case "Tan"

                result = Math.Tan(total1 / conversionFactor)

        End Select

        answer.Text = result

    End Sub 

| Iswandi阿卜杜勒・拉赫曼