VB.net 文本框中数字的随机位置

Question

所以这只是我的问题的延续VB.Net grade distribution exercise

但我现在想做的是在单击按钮时交换或随机化它们的位置。

这就是我正在做的事情：

    If txtGrade.Text <> "" Then
        If CDbl(txtGrade.Text) Then
            txtA.Text = (CDbl(txtGrade.Text) * 40) / 100
            txtB.Text = (CDbl(txtGrade.Text) * 20) / 100
            txtC.Text = (CDbl(txtGrade.Text) * 30) / 100
            txtD.Text = (CDbl(txtGrade.Text) * 10) / 100
        End If
    End If

更新： 我把上面的代码放在 txtGrade_TextChanged 事件上

但我真的不知道如何随机化他们的位置。有任何想法吗？谢谢。

Answer 1

使用Random 类：（经过编辑以显示更简洁的版本）

Dim grade As Double
If Double.TryParse(txtGrade.Text, grade) Then
    Dim values = {(grade * 40 / 100).ToString(), (grade * 20 / 100).ToString(), (grade * 30 / 100).ToString(), (grade * 10 / 100).ToString()}
    FillRandomControlText({txtA, txtB, txtC, txtD}, values)
End If

用这个方法：

Shared Sub FillRandomControlText(txtControls As IList(Of TextBox), values As IList(Of String))
    Dim rnd = New Random()
    Dim txt As TextBox
    Dim selectedControls = New List(Of Control)(txtControls.Count)
    For i As Int32 = 0 To txtControls.Count - 1
        Do
            txt = txtControls(rnd.Next(txtControls.Count))
        Loop While selectedControls.Contains(txt)
        selectedControls.Add(txt)
        txt.Text = values(i)
    Next
End Sub

暗淡等级为双 Dim rnd = 新随机（） 昏暗控件 = {txtA, txtB, txtC, txtD} 暗淡 selectedControls = 新列表（控制） 将 txt 调暗为文本框

If Double.TryParse(txtGrade.Text, grade) Then
    Do
        txt = controls(rnd.Next(controls.Length))
    Loop While selectedControls.Contains(txt)
    selectedControls.Add(txt)
    txt.Text = (grade * 40 / 100).ToString()
    Do
        txt = controls(rnd.Next(controls.Length))
    Loop While selectedControls.Contains(txt)
    selectedControls.Add(txt)
    txt.Text = (grade * 20 / 100).ToString()
    Do
        txt = controls(rnd.Next(controls.Length))
    Loop While selectedControls.Contains(txt)
    selectedControls.Add(txt)
    txt.Text = (grade * 30 / 100).ToString()
    Do
        txt = controls(rnd.Next(controls.Length))
    Loop While selectedControls.Contains(txt)
    txt.Text = (grade * 10 / 100).ToString()
End If

Answer 2

单击按钮后，您需要将要交换/随机化/随机播放的值存储到 List(Of T) 中，如下所示：

Dim ValuesToShuffle = New List(Of String)
ValuesToShuffle.Add(txtA.Text)
ValuesToShuffle.Add(txtB.Text)
ValuesToShuffle.Add(txtC.Text)
ValuesToShuffle.Add(txtD.Text)

现在您将循环遍历这些值，以每次随机生成一个随机数并移动值，如下所示：

Dim rand = New Random()

For counter = 0 to ValuesToShuffle.Count- 1
    Dim n = rand.Next(counter + 1)
    Dim temp = ValuesToShuffle(counter)
    ValuesToShuffle(counter) = ValuesToShuffle(n)
    ValuesToShuffle(n) = temp
Next

最后，将洗牌后的值放回文本框中，如下所示：

txtA.Text = ValuesToShuffle(0)
txtB.Text = ValuesToShuffle(1)
txtC.Text = ValuesToShuffle(2)
txtD.Text = ValuesToShuffle(3)