Visual Basic - 使用并行数组根据用户输入的输入显示运费

Question

我真的很讨厌使用数组。我有一个二维数组，但无法弄清楚如何使用并行一维数组。 “显示运输”按钮的“单击偶数”应根据用户输入的项目数显示运费。我将最小订单金额和运费存储在并行数组中。我无法让计算正常工作。任何帮助表示赞赏。

Public Class frmMain
    'declare parallel arrays
    Private strNums() As String = {"1", "11", "51", "101"}
    Private intShipping() As Integer = {15, 10, 5, 0}

    Private Sub btnExit_Click(sender As Object, e As EventArgs) Handles btnExit.Click
        Me.Close()
    End Sub

    Private Sub txtordered_KeyPress(sender As Object, e As KeyPressEventArgs) Handles txtOrdered.KeyPress
        ' allows the text box to accept numbers and the Backspace key

        If (e.KeyChar < "0" OrElse e.KeyChar > "9") AndAlso e.KeyChar <> ControlChars.Back Then
            e.Handled = True
        End If
    End Sub

    Private Sub txtordered_TextChanged(sender As Object, e As EventArgs) Handles txtOrdered.TextChanged
        lblShipping.Text = String.Empty
    End Sub

    Private Sub btnDisplay_Click(sender As Object, e As EventArgs) Handles btnDisplay.Click
        'displays the shipping price based on orders
        Dim strSearchForNum As Integer
        Dim intSub As Integer

        Integer.TryParse(txtOrdered.Text, strSearchForNum)

        'search the array for the orders greater than zero
        'if less than zero show error message
        'otherwise display shipping charge

        Do Until intSub >= strNums.Length OrElse
          strSearchForNum >= CDbl(strNums(intSub))
            intSub += 1
        Loop
        If strSearchForNum = 0 Then
            MessageBox.Show("Please enter a number greater than 0", "Number of Orders")
        Else
            lblShipping.Text = intShipping(intSub).ToString("C2")

        End If

        txtOrdered.Focus()
    End Sub
End Class