Visual Basic解數學之一 : 華式溫度與攝氏溫度的互換

作者: Fred Wang (FW知識瑣記) 日期: 20140706

適用版本: VB2010~2013

功能
1. 選擇不同功能(轉換方式), Form的標題與 Label1, Label2的文字會跟著改變
    例如選擇"攝氏轉華氏"標題會變成"攝氏溫度轉華氏溫度", Label1的文字會變成

"攝氏溫度", Label2的文字會變成"華氏溫度"

2.按"執行"按鈕(ButtonRun)後,會檢查Textbox1是否輸入的是數值, 並執行計算,在Textbox2中顯示結果

3.按"離開"按鈕(ButtonQuit)後,會結束程式 

程式碼參考如下

Public Class Form1

    Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        TextBox1.Focus()
    End Sub

    Private Sub RadioButton2_CheckedChanged(sender As Object, e As EventArgs) Handles RadioButton2.CheckedChanged
        Me.Text = "攝氏溫度轉華氏溫度"
        Label1.Text = "攝氏溫度"
        Label2.Text = "華氏溫度"
    End Sub

    Private Sub RadioButton1_CheckedChanged(sender As Object, e As EventArgs) Handles RadioButton1.CheckedChanged
        Me.Text = "華氏溫度轉攝氏溫度"
        Label1.Text = "華氏溫度"
        Label2.Text = "攝氏溫度"
    End Sub

    Private Sub ButtonQuit_Click(sender As Object, e As EventArgs) Handles ButtonQuit.Click
        End
    End Sub

    Private Sub ButtonRun_Click(sender As Object, e As EventArgs) Handles ButtonRun.Click
        If Not IsNumeric(TextBox1.Text) Then
            MsgBox("請輸入數字", MsgBoxStyle.OkOnly)
        Else
            If RadioButton1.Checked Then
                TextBox2.Text = CStr((5 / 9) * (Val(TextBox1.Text) - 32))
            Else
                TextBox2.Text = CStr((9 / 5) * Val(TextBox1.Text) + 32)
            End If
        End If
    End Sub
End Class

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