Question

我在for-next-statement中创建了3个随机字节。

但是，对于每个for-next，它们总是相同的，例如“333”或“777”。

我想知道为什么会这样，我做错了什么。

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

    Dim s As String = String.Empty

    For i As Integer = 0 To 2
        s += GetRandomByte().ToString
    Next

    Me.TextBox1.Text = s

End Sub

Public Function GetRandomByte(Optional ByVal uLow As Byte = 1, Optional ByVal uHigh As Byte = 9) As Byte

    Dim r As New Random
    Dim b As Integer = r.Next(CInt(uLow), CInt(uHigh + 1))

    Return b

End Function

Answer 1

在新Random的构造函数中，每次都给它一个新的种子。我喜欢使用当前时间戳的哈希码值

New Random(Now.GetHashCode)

Answer 2

为所有来电保留相同的实例：

Dim r As New Random()

Public Function GetRandomByte(Optional ByVal uLow As Byte = 1, Optional ByVal uHigh As Byte = 9) As Byte
    Return r.Next(CInt(uLow), CInt(uHigh + 1))
End Function

或者，向种子传递给种子：

Dim r As New Random(CInt(Date.Now.Ticks And &h0000FFFF))

For-Next-Statement中的新随机重复相同的值

2 个答案: