用于随机数生成器的 Visual Basic 文本框数组 - 家庭作业

Question

我想做一个随机数生成器。是为了学校作业。我似乎无法让它工作。

任务是制作一个随机数生成器，将 20 个数字生成到 20 个文本框中，以提出 10 个数学问题。

它需要尽可能高效。我需要帮助，因为我只能这样做，但它确实效率低下且代码很长。

Dim RandomNumberAHigh As Integer = 12 'Here I am declaring my highest number for the random number generator to use. This will be the highest number the maths quiz will ask the students in the questions.
Dim RandomNumberALow As Integer = 1 'Here I am declaring my lowest number for the random number generator to use. This will be the lowest number the maths quiz will ask the students in the questions.
Dim Random As Integer = 0 'Her I am declaring a variable that will be used to insert the numbers from the random number generator in the quiz text boxes.
Randomize()
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd1.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd4.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd7.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd10.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd13.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd16.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd19.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd22.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd25.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd28.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd3.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd6.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd9.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd12.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd15.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd18.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd21.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd24.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd27.Text = (Random)
Random = Int((RandomNumberAHigh - RandomNumberALow + 1) * Rnd() + RandomNumberALow)
Rnd30.Text = (Random)

Answer 1

“高效”是相当主观的。有许多方法可以做到这一点：

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    RandomizeTextBoxes(1, 12)
End Sub

Private Sub RandomizeTextBoxes(ByVal Low As Integer, ByVal High As Integer)
    Static R As New Random
    For i As Integer = 1 To 30
        Dim matches() As Control = Me.Controls.Find("Rnd" & i, True)
        If matches.Length > 0 AndAlso TypeOf matches(0) Is TextBox Then
            DirectCast(matches(0), TextBox).Text = R.Next(Low, High + 1)
        End If
    Next
End Sub

Answer 2

就像@Idle_Mind 的回答一样，它使用文本框的 Name 属性来确定是否应该为 Text 属性分配生成的值。

这里的区别是我是通过控件集合来枚举的；在 For Each 循环中使用 IEnumerable。通过这种方式，我不必检查控件集合、对照控件集合的长度，或者在循环处理中强制转换控件。

Sub RandomizeTextBoxes(min As Integer, max As Integer)
    Dim r As Random = New Random()
    Dim RandomTextboxes As IEnumerable(Of TextBox) = Me.Controls.OfType(Of TextBox).Where(AddressOf DoesTextboxNameContainRnd)
    For Each tbControl As TextBox In RandomTextboxes
        tbControl.Text = r.Next(min, max)
    Next
End Sub

Function DoesTextboxNameContainRnd(tbControl As TextBox) As Boolean
    Return tbControl.Name.Contains("Rnd")
End Function

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    RandomizeTextBoxes(1, 50)
End Sub