Question

  Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

    If Val(TextBox5.Text) = 0 Then
        TextBox5.Text = 0
    End If

    TextBox5.Text = TextBox5.Text + 1
    Dim percent As Double
    percent = (TextBox3.Text) / 100      
    Dim value As Integer = Integer.Parse(TextBox1.Text)
    Dim flag As Integer = 0
    Dim count As Integer = 0
    Do While count < value
        Dim rnd = New Random()
        Dim nextValue = rnd.Next(100) / 100
        If nextValue < percent Then
            flag = flag + 1
        End If
        count = count + 1
    Loop
    TextBox6.Text = value - flag
End Sub

如果我一步一步地调试控件进入循环我的代码工作正常。但是当我直接执行它时，控件不会进入循环

Answer 1

Dim value As Integer = Integer.Parse（TextBox1.Text）

请确保TextBox1具有非零积分值。

Answer 2

以下将产生更好的结果：

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click

    If Val(TextBox5.Text) = 0 Then
        TextBox5.Text = 0
    End If

    TextBox5.Text += 1
    Dim percent As Double = (TextBox3.Text) / 100  
    Dim value As Integer = Integer.Parse(TextBox1.Text)
    Dim flag As Integer = 0
    Dim count As Integer = 0
    Dim rnd = New Random() 'Move this out of the loop
    Do While count < value
        Dim nextValue = rnd.Next(100) / 100
        If nextValue < percent Then
            flag += 1
        End If
        count += 1
    Loop
    TextBox6.Text = value - flag
End Sub

将Dim rnd移出循环会停止代码在每次循环执行时创建一个新的随机对象，这意味着您获得了更好的结果，就像使用代码一样，获得{{1} } = TextBox6.Text或value = 0

同样使用TextBox6.Text而不是object.Value += 1更整洁，并且可以在大循环中提高执行速度。

代码不会进入For循环或Do while循环

2 个答案: