用于 VB.Net 中任何双面骰子的骰子滚轮

Question

我想创建一个骰子滚轮，以便用户可以选择骰子上的多个面，它会随机响应，我当前的代码总是抛出相同的数字。

Sub rollDie(ByVal sides As Integer)
    Dim rand As Single = Rnd()
    For cnt As Integer = 1 To sides
        If rand < cnt / sides Then
            diceRoll = cnt
            Exit For
        End If
    Next
    Console.WriteLine("You rolled a {0} sided die which landed on {1}", sides, diceRoll)
End Sub

Answer 1

我认为您最好将所有 Die 逻辑放入一个类中并使用 System.Random 类为您生成随机数，如下所示：

Public Class Die
    Private _sides As Integer
    Private Shared _generator As New System.Random '<<<one PRNG no matter how many dice

    Public ReadOnly Property Sides As Integer
        Get
            Return _sides
        End Get
    End Property

    Public Sub New(sides As Integer)
        _sides = sides
    End Sub

    ''' <summary>
    ''' Returns a random number between 1 and the number of sides of the die
    ''' </summary>
    ''' <returns></returns>
    ''' <remarks></remarks>
    Public Function Roll() As Integer
        Return _generator.Next(1, _sides + 1)
    End Function
End Class

那么你可以这样使用它：

Dim elevensidedDie As New Die(11)
Debug.WriteLine("You rolled a(n) {0} sided die which landed on {1}", elevensidedDie.Sides, elevensidedDie.Roll)

Answer 2

您应该使用 VB.Net 的 Randomize function 来播种随机数生成器，即

Sub rollDie(ByVal sides As Integer)
Randomize()
Dim rand As Single = Rnd()
For cnt As Integer = 1 To sides
    If rand < cnt / sides Then
        diceRoll = cnt
        Exit For
    End If
Next
Console.WriteLine("You rolled a {0} sided die which landed on {1}", sides, diceRoll)
End Sub

Randomize 函数将系统计时器用于种子。您可以在程序开始或rollDie 函数中调用它。

Answer 3

使用循环是一种非常低效的生成随机整数的方法。查看this 页面以获得更好的方法。

这是与 cmets 最相关的部分的副本：

' Initialize the random-number generator.
Randomize()
' Generate random value between 1 and 6. 
Dim value As Integer = CInt(Int((6 * Rnd()) + 1))

更简洁，也更快。