Question

如果用户输入的术语小于50或大于1，则必须让程序显示错误，因此中间的任何内容都是错误。用户必须键入50+或0才能收到错误。我几乎是肯定的，直到我仔细看了一下这个项目。输入任何数字时都会收到错误。

    Const strMSG As String = "The term must be less than 1 or greater than 50."
    Const strMSG2 As String = "The term must be less than 1 or greater than 50."

    txtOwed.Text = FormatCurrency(txtRegistrants.Text * 80)
    If txtOwed.Text > 50 Then
        txtOwed.Text = txtOwed.Text
    Else
        MessageBox.Show(strMSG, "Monthly Payment Calculator", _
                        MessageBoxButtons.OK, MessageBoxIcon.Information)
    End If

    If txtOwed.Text < 1 Then
        txtOwed.Text = txtOwed.Text
    Else
        MessageBox.Show(strMSG2, "Monthly Payment Calculator", _
                        MessageBoxButtons.OK, MessageBoxIcon.Information)
    End If

Answer 1

将您的代码更改为以下内容：

If val(txtOwed.Text) > 1 and val(txtOwed.Text) < 50 Then
  MessageBox.Show(strMSG, "Monthly Payment Calculator", _
                    MessageBoxButtons.OK, MessageBoxIcon.Information)
End If

请注意，我解决了您的主题，而不是您附上的措辞和示例代码

Answer 2

我认为这对大多数人来说最容易理解：

If not(txtOwed.Text > 50 or txtOwed.text = 0) Then
    MessageBox.Show(strMSG, "Monthly Payment Calculator", _
                    MessageBoxButtons.OK, MessageBoxIcon.Information)
End If

但

not(txtOwed.Text > 50 or txtOwed.text = 0)

相当于

(txtOwed.Text <= 50 and txtOwed.text <> 0)

代码要求你弹出一个错误，如果它大于1，小于50？

2 个答案: