VB：Random Shuffler Duplicating Values

Question

我试图做一个交易或不交易的游戏，但是我现在的问题是随机为案例分配设置值。我没有随机生成一个数字并检查它是否已经存在，所以我现在试图简单地洗牌数组。问题是，出于某种原因，值重复。 代码：

Dim nCaseValues(26) As Integer 'The different possible values for a case 
    Dim nCaseNumbers(26) As Integer 'The different case numbers 

    Dim nShadowNumber As Integer 'This holds the first number in the shuffle 
    Dim nShuffleNumber1 As Integer 'The first random position 
    Dim nShuffleNumber2 As Integer 'The second random position 

    'Clear the list if it already has content 
    listArray1.Items.Clear() 
    listArray2.Items.Clear() 
    listArray3.Items.Clear() 

    'Declare array for case values 
    nCaseValues(0) = 1500 
    nCaseValues(1) = 1 
    nCaseValues(2) = 2 
    nCaseValues(3) = 5 
    nCaseValues(4) = 10 
    nCaseValues(5) = 20 
    nCaseValues(6) = 50 
    nCaseValues(7) = 100 
    nCaseValues(8) = 150 
    nCaseValues(9) = 200 
    nCaseValues(10) = 250 
    nCaseValues(11) = 500 
    nCaseValues(12) = 750 
    nCaseValues(13) = 1000 
    nCaseValues(14) = 2000 
    nCaseValues(15) = 3000 
    nCaseValues(16) = 4000 
    nCaseValues(17) = 5000 
    nCaseValues(18) = 10000 
    nCaseValues(19) = 15000 
    nCaseValues(20) = 20000 
    nCaseValues(21) = 30000 
    nCaseValues(22) = 50000 
    nCaseValues(23) = 75000 
    nCaseValues(24) = 100000 
    nCaseValues(25) = 200000 

    'Declare array for case numbers 
    For genCaseNumArray = 0 To 25 
     nCaseNumbers(genCaseNumArray) = 0 
     listArray1.Items.Add(genCaseNumArray) 
    Next 

'The shuffle 
    For J = 0 To 25 'This assigns case values to case numbers (It's probably moot, as I can just use the nCaseValues position, but it's here for now) 
     nCaseNumbers(J) = nCaseValues(J) 
    Next 
    For K = 0 To 25 'Lists the items below, this could possibly be an error 

     For I = 0 To 50 'Shuffles the list 50 times 
      nShuffleNumber1 = (Int(Rnd() * 26)) 'Gets a random number and assigns it 
      nShuffleNumber2 = (Int(Rnd() * 26))'Gets a random number and assigns it 
      nShadowNumber = nCaseNumbers(nShuffleNumber1) 'This holds the first value during the shuffle 
      nCaseNumbers(nShuffleNumber1) = nCaseNumbers(nShuffleNumber2)'First value now equals second value... 
      nCaseNumbers(nShuffleNumber2) = nShadowNumber 'And now second value holds first value. 

     Next 'Lists items in lists objects on the form 
     listArray1.Items.Add(K) 
     listArray2.Items.Add(nCaseValues(K)) 
     listArray3.Items.Add(nCaseNumbers(K)) 
    Next 

我需要每个值是唯一的。我很确定这是我的代码中的逻辑错误。任何关于数字为什么重复的帮助都会很好。

这里有一对夫妇的输出：

第一清单的案件编号，二是为了可能的值，第三个是最终的结局 - 个案价值。正如你所看到的，一些是重复的，第一个列表重复两次..编辑：我发现它为什么重复两次 - 我很愚蠢，留下另一个循环，这也是添加到列表中。我已经解决了我的问题，请参阅下面的答案。

Answer 1

我曾经推荐随机化一个这样的数组：

Dim rng As New Random 

myArray = myArray.OrderBy(Function(element) rng.NextDouble()).ToArray() 

此后，它一直向我指出，有与一个严重的问题，因为它会产生多个相同的元素一个新的随机数次，因此比较相同的两个元素可以在不同的场合产生不同的结果。还有一个问题是它创建一个新的数组对象。下面克服了这两个问题的那些：

Dim rng As New Random 
Dim keys = myArray.Select(Function(element) rng.NextDouble()).ToArray() 

Array.Sort(keys, myArray) 

即生成每一个元素的随机数，然后通过排序这些密钥就地原始数组。

Answer 2

我想出了问题（好吧，更多的只是运气） - 内部For循环应该不是的内部。我把它搬出去，瞧 - 它就像一个魅力一样。至今。让我们等待。

Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load 
    Randomize() 'Make the form random 

End Sub 

Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click 
    'State Variables 
    Dim nCaseValues(26) As Integer 'The different possible values for a case 
    Dim nShadowNumber As Integer 
    Dim nShuffleNumber1 As Integer 
    Dim nShuffleNumber2 As Integer 

    'Clear the list if it already has content 
    listArray1.Items.Clear() 
    listArray2.Items.Clear() 
    listArray3.Items.Clear() 

    'Declare array for case values 
    nCaseValues(0) = 1500 'If you're wondering why this is here, it's because I couldn't be bothered to work with a "car" value. 
    nCaseValues(1) = 1 
    nCaseValues(2) = 2 
    nCaseValues(3) = 5 
    nCaseValues(4) = 10 
    nCaseValues(5) = 20 
    nCaseValues(6) = 50 
    nCaseValues(7) = 100 
    nCaseValues(8) = 150 
    nCaseValues(9) = 200 
    nCaseValues(10) = 250 
    nCaseValues(11) = 500 
    nCaseValues(12) = 750 
    nCaseValues(13) = 1000 
    nCaseValues(14) = 2000 
    nCaseValues(15) = 3000 
    nCaseValues(16) = 4000 
    nCaseValues(17) = 5000 
    nCaseValues(18) = 10000 
    nCaseValues(19) = 15000 
    nCaseValues(20) = 20000 
    nCaseValues(21) = 30000 
    nCaseValues(22) = 50000 
    nCaseValues(23) = 75000 
    nCaseValues(24) = 100000 
    nCaseValues(25) = 200000 

    'Declare array for case numbers, probably obsolete 
    For genCaseNumArray = 0 To 25 
     nCaseNumbers(genCaseNumArray) = 0 
    Next 

    For J = 0 To 25 'Assigning case values to case numbers 
     nCaseNumbers(J) = nCaseValues(J) 
    Next 

    For I = 0 To 26 'The main shuffle. 
     nShuffleNumber1 = (Int(Rnd() * 26)) 'This selects a random number between 0 and 25, somehow. 
     nShuffleNumber2 = (Int(Rnd() * 26)) 'Ditto 
     nShadowNumber = nCaseNumbers(nShuffleNumber1) 'This "Shadow Number" will be used to temporarily hold the value of the first case 
     nCaseNumbers(nShuffleNumber1) = nCaseNumbers(nShuffleNumber2) 'The value of the first case now equals the value of the second case... 
     nCaseNumbers(nShuffleNumber2) = nShadowNumber '... and vice versa. 

    Next 'Display the cases, case values and shuffled case values in the lists. 
    For K = 0 To 25 
     listArray1.Items.Add(K) 
     listArray2.Items.Add(nCaseValues(K)) 
     listArray3.Items.Add(nCaseNumbers(K)) 
    Next 

我发现这是一个非常简单的和（也许）洗牌阵列的有效方式。比为MERN编写脚本要容易得多。