VBA Rnd（）函数通常用于生成“随机”数字。 当然，您无法使用任何程序算法生成真正的随机数。 但是某些伪随机数生成器算法要比其他算法好。 本文讨论了为什么本机PRNG不好的原因，以及在真正需要“随机性”的情况下可以使用的替代方法。

VBA如何生成其随机数

资源：

https://support.microsoft.com/zh-CN/kb/231847

虽然以上链接的文章适用于VB 6.0，但VBA基于相同的代码库。 通过手动计算VB 6.0算法中的前几个数字并将其与VBA输出进行比较，我可以确认它使用了相同的算法。

基本上，它使用递归函数来生成其随机数。

x1 = ( x0 * 1140671485 + 12820163 ) MOD (2^24)
return x1 / (2^24)

第一次运行时x0 = 327680，否则，使用先前计算的值。 问题

Rnd（）实现的一个问题是周期短，这意味着它在开始重复之前可以生成的数量。 生成2 ^ 24个数字后，它将开始重复数字。

另一个问题是它是串行相关的。 这意味着了解函数的前几个输出将揭示可用于预测未来输出的信息。 如果可以开始预测其“随机”输出，就不能真正调用随机的东西。

对于某些应用程序来说，这不是问题，但如果您确实需要随机数，则可能会带来问题。 例如，如果仅使用它来生成一个小的随机样本以将总体分为两组，则可能无关紧要。 但这是一个主要问题，如果您想为彩票游戏生成随机数。

解决方案

虽然还有许多其他PRNG算法，例如

Mersenne Twister ，您可以实现不会受到这些问题困扰的解决方案，我的解决方案基于已经拥有的代码库：加密算法。

基本上，密码学是一种精美的PRNG。 密码学的目的是获取密码（即种子）并将其用于将数据编码为不可预测的（即伪随机）形式。

因此，您可以采用任何足够强大的加密算法并将其转换为PRNG。 执行此操作的方法是在计数器模式下运行算法。 也就是说，当您要开始生成随机数时，可以使用种子作为密码，并从数字0开始加密。然后对数字1进行加密，然后对2进行加密，依此类推。 当然，您可以以任何数字开头，而不必每次都加1。 这只是简单的例子。

编码

以下代码是在计数器模式下使用zmbd的VBScript AES代码的VBA实现的示例实现。

AES代码略有修改，以将纯文本输入作为字符串而不是文件。 由于一次只能编码1个块，因此已删除了一些循环。

您可以删除其他加密算法来代替AES函数，只要它产生至少8个字节的字符串输出即可。 AES每个块产生一个16字节的输出，因此此实现会丢弃最后8个字节，以避免溢出双精度型。

https://bytes.com/topic/access/insig...m-vba-vbscript

Option Compare Database
Option Explicit
Dim iSeed As Double
Dim iCounter As Double
Function RNG(seed As Double)Dim sCounter As String, sPassin As StringDim i As Integer, sResult As String, dResult As Double If iSeed <> seed TheniCounter = 0End If iSeed = seediCounter = iCounter + 1sCounter = ""sPassin = "" For i = 0 To 7sPassin = sPassin & Chr((iSeed / (256 ^ i)) And 255)sCounter = sCounter & Chr((iCounter / (256 ^ i)) And 255)Next sResult = RunAES(sCounter, sPassin)dResult = 0 For i = 1 To 8dResult = dResult + Asc(Mid(sResult, i, 1)) * (256 ^ (i - 1))Next RNG = dResult / (256 ^ 8)
End Function
Function RunAES(sCounter, sPassin)Dim sbox(), sboxinv(), rcon()Dim g2, g3, g9, g11, g13, g14 g2 = Array( _&H0, &H2, &H4, &H6, &H8, &HA, &HC, &HE, &H10, &H12, &H14, &H16, &H18, &H1A, &H1C, &H1E, _&H20, &H22, &H24, &H26, &H28, &H2A, &H2C, &H2E, &H30, &H32, &H34, &H36, &H38, &H3A, &H3C, &H3E, _&H40, &H42, &H44, &H46, &H48, &H4A, &H4C, &H4E, &H50, &H52, &H54, &H56, &H58, &H5A, &H5C, &H5E, _&H60, &H62, &H64, &H66, &H68, &H6A, &H6C, &H6E, &H70, &H72, &H74, &H76, &H78, &H7A, &H7C, &H7E, _&H80, &H82, &H84, &H86, &H88, &H8A, &H8C, &H8E, &H90, &H92, &H94, &H96, &H98, &H9A, &H9C, &H9E, _&HA0, &HA2, &HA4, &HA6, &HA8, &HAA, &HAC, &HAE, &HB0, &HB2, &HB4, &HB6, &HB8, &HBA, &HBC, &HBE, _&HC0, &HC2, &HC4, &HC6, &HC8, &HCA, &HCC, &HCE, &HD0, &HD2, &HD4, &HD6, &HD8, &HDA, &HDC, &HDE, _&HE0, &HE2, &HE4, &HE6, &HE8, &HEA, &HEC, &HEE, &HF0, &HF2, &HF4, &HF6, &HF8, &HFA, &HFC, &HFE, _&H1B, &H19, &H1F, &H1D, &H13, &H11, &H17, &H15, &HB, &H9, &HF, &HD, &H3, &H1, &H7, &H5, _&H3B, &H39, &H3F, &H3D, &H33, &H31, &H37, &H35, &H2B, &H29, &H2F, &H2D, &H23, &H21, &H27, &H25, _&H5B, &H59, &H5F, &H5D, &H53, &H51, &H57, &H55, &H4B, &H49, &H4F, &H4D, &H43, &H41, &H47, &H45, _&H7B, &H79, &H7F, &H7D, &H73, &H71, &H77, &H75, &H6B, &H69, &H6F, &H6D, &H63, &H61, &H67, &H65, _&H9B, &H99, &H9F, &H9D, &H93, &H91, &H97, &H95, &H8B, &H89, &H8F, &H8D, &H83, &H81, &H87, &H85, _&HBB, &HB9, &HBF, &HBD, &HB3, &HB1, &HB7, &HB5, &HAB, &HA9, &HAF, &HAD, &HA3, &HA1, &HA7, &HA5, _&HDB, &HD9, &HDF, &HDD, &HD3, &HD1, &HD7, &HD5, &HCB, &HC9, &HCF, &HCD, &HC3, &HC1, &HC7, &HC5, _&HFB, &HF9, &HFF, &HFD, &HF3, &HF1, &HF7, &HF5, &HEB, &HE9, &HEF, &HED, &HE3, &HE1, &HE7, &HE5) g3 = Array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g9 = Array( _&H0, &H9, &H12, &H1B, &H24, &H2D, &H36, &H3F, &H48, &H41, &H5A, &H53, &H6C, &H65, &H7E, &H77, _&H90, &H99, &H82, &H8B, &HB4, &HBD, &HA6, &HAF, &HD8, &HD1, &HCA, &HC3, &HFC, &HF5, &HEE, &HE7, _&H3B, &H32, &H29, &H20, &H1F, &H16, &HD, &H4, &H73, &H7A, &H61, &H68, &H57, &H5E, &H45, &H4C, _&HAB, &HA2, &HB9, &HB0, &H8F, &H86, &H9D, &H94, &HE3, &HEA, &HF1, &HF8, &HC7, &HCE, &HD5, &HDC, _&H76, &H7F, &H64, &H6D, &H52, &H5B, &H40, &H49, &H3E, &H37, &H2C, &H25, &H1A, &H13, &H8, &H1, _&HE6, &HEF, &HF4, &HFD, &HC2, &HCB, &HD0, &HD9, &HAE, &HA7, &HBC, &HB5, &H8A, &H83, &H98, &H91, _&H4D, &H44, &H5F, &H56, &H69, &H60, &H7B, &H72, &H5, &HC, &H17, &H1E, &H21, &H28, &H33, &H3A, _&HDD, &HD4, &HCF, &HC6, &HF9, &HF0, &HEB, &HE2, &H95, &H9C, &H87, &H8E, &HB1, &HB8, &HA3, &HAA, _&HEC, &HE5, &HFE, &HF7, &HC8, &HC1, &HDA, &HD3, &HA4, &HAD, &HB6, &HBF, &H80, &H89, &H92, &H9B, _&H7C, &H75, &H6E, &H67, &H58, &H51, &H4A, &H43, &H34, &H3D, &H26, &H2F, &H10, &H19, &H2, &HB, _&HD7, &HDE, &HC5, &HCC, &HF3, &HFA, &HE1, &HE8, &H9F, &H96, &H8D, &H84, &HBB, &HB2, &HA9, &HA0, _&H47, &H4E, &H55, &H5C, &H63, &H6A, &H71, &H78, &HF, &H6, &H1D, &H14, &H2B, &H22, &H39, &H30, _&H9A, &H93, &H88, &H81, &HBE, &HB7, &HAC, &HA5, &HD2, &HDB, &HC0, &HC9, &HF6, &HFF, &HE4, &HED, _&HA, &H3, &H18, &H11, &H2E, &H27, &H3C, &H35, &H42, &H4B, &H50, &H59, &H66, &H6F, &H74, &H7D, _&HA1, &HA8, &HB3, &HBA, &H85, &H8C, &H97, &H9E, &HE9, &HE0, &HFB, &HF2, &HCD, &HC4, &HDF, &HD6, _&H31, &H38, &H23, &H2A, &H15, &H1C, &H7, &HE, &H79, &H70, &H6B, &H62, &H5D, &H54, &H4F, &H46) g11 = Array( _&H0, &HB, &H16, &H1D, &H2C, &H27, &H3A, &H31, &H58, &H53, &H4E, &H45, &H74, &H7F, &H62, &H69, _&HB0, &HBB, &HA6, &HAD, &H9C, &H97, &H8A, &H81, &HE8, &HE3, &HFE, &HF5, &HC4, &HCF, &HD2, &HD9, _&H7B, &H70, &H6D, &H66, &H57, &H5C, &H41, &H4A, &H23, &H28, &H35, &H3E, &HF, &H4, &H19, &H12, _&HCB, &HC0, &HDD, &HD6, &HE7, &HEC, &HF1, &HFA, &H93, &H98, &H85, &H8E, &HBF, &HB4, &HA9, &HA2, _&HF6, &HFD, &HE0, &HEB, &HDA, &HD1, &HCC, &HC7, &HAE, &HA5, &HB8, &HB3, &H82, &H89, &H94, &H9F, _&H46, &H4D, &H50, &H5B, &H6A, &H61, &H7C, &H77, &H1E, &H15, &H8, &H3, &H32, &H39, &H24, &H2F, _&H8D, &H86, &H9B, &H90, &HA1, &HAA, &HB7, &HBC, &HD5, &HDE, &HC3, &HC8, &HF9, &HF2, &HEF, &HE4, _&H3D, &H36, &H2B, &H20, &H11, &H1A, &H7, &HC, &H65, &H6E, &H73, &H78, &H49, &H42, &H5F, &H54, _&HF7, &HFC, &HE1, &HEA, &HDB, &HD0, &HCD, &HC6, &HAF, &HA4, &HB9, &HB2, &H83, &H88, &H95, &H9E, _&H47, &H4C, &H51, &H5A, &H6B, &H60, &H7D, &H76, &H1F, &H14, &H9, &H2, &H33, &H38, &H25, &H2E, _&H8C, &H87, &H9A, &H91, &HA0, &HAB, &HB6, &HBD, &HD4, &HDF, &HC2, &HC9, &HF8, &HF3, &HEE, &HE5, _&H3C, &H37, &H2A, &H21, &H10, &H1B, &H6, &HD, &H64, &H6F, &H72, &H79, &H48, &H43, &H5E, &H55, _&H1, &HA, &H17, &H1C, &H2D, &H26, &H3B, &H30, &H59, &H52, &H4F, &H44, &H75, &H7E, &H63, &H68, _&HB1, &HBA, &HA7, &HAC, &H9D, &H96, &H8B, &H80, &HE9, &HE2, &HFF, &HF4, &HC5, &HCE, &HD3, &HD8, _&H7A, &H71, &H6C, &H67, &H56, &H5D, &H40, &H4B, &H22, &H29, &H34, &H3F, &HE, &H5, &H18, &H13, _&HCA, &HC1, &HDC, &HD7, &HE6, &HED, &HF0, &HFB, &H92, &H99, &H84, &H8F, &HBE, &HB5, &HA8, &HA3) g13 = Array( _&H0, &HD, &H1A, &H17, &H34, &H39, &H2E, &H23, &H68, &H65, &H72, &H7F, &H5C, &H51, &H46, &H4B, _&HD0, &HDD, &HCA, &HC7, &HE4, &HE9, &HFE, &HF3, &HB8, &HB5, &HA2, &HAF, &H8C, &H81, &H96, &H9B, _&HBB, &HB6, &HA1, &HAC, &H8F, &H82, &H95, &H98, &HD3, &HDE, &HC9, &HC4, &HE7, &HEA, &HFD, &HF0, _&H6B, &H66, &H71, &H7C, &H5F, &H52, &H45, &H48, &H3, &HE, &H19, &H14, &H37, &H3A, &H2D, &H20, _&H6D, &H60, &H77, &H7A, &H59, &H54, &H43, &H4E, &H5, &H8, &H1F, &H12, &H31, &H3C, &H2B, &H26, _&HBD, &HB0, &HA7, &HAA, &H89, &H84, &H93, &H9E, &HD5, &HD8, &HCF, &HC2, &HE1, &HEC, &HFB, &HF6, _&HD6, &HDB, &HCC, &HC1, &HE2, &HEF, &HF8, &HF5, &HBE, &HB3, &HA4, &HA9, &H8A, &H87, &H90, &H9D, _&H6, &HB, &H1C, &H11, &H32, &H3F, &H28, &H25, &H6E, &H63, &H74, &H79, &H5A, &H57, &H40, &H4D, _&HDA, &HD7, &HC0, &HCD, &HEE, &HE3, &HF4, &HF9, &HB2, &HBF, &HA8, &HA5, &H86, &H8B, &H9C, &H91, _&HA, &H7, &H10, &H1D, &H3E, &H33, &H24, &H29, &H62, &H6F, &H78, &H75, &H56, &H5B, &H4C, &H41, _&H61, &H6C, &H7B, &H76, &H55, &H58, &H4F, &H42, &H9, &H4, &H13, &H1E, &H3D, &H30, &H27, &H2A, _&HB1, &HBC, &HAB, &HA6, &H85, &H88, &H9F, &H92, &HD9, &HD4, &HC3, &HCE, &HED, &HE0, &HF7, &HFA, _&HB7, &HBA, &HAD, &HA0, &H83, &H8E, &H99, &H94, &HDF, &HD2, &HC5, &HC8, &HEB, &HE6, &HF1, &HFC, _&H67, &H6A, &H7D, &H70, &H53, &H5E, &H49, &H44, &HF, &H2, &H15, &H18, &H3B, &H36, &H21, &H2C, _&HC, &H1, &H16, &H1B, &H38, &H35, &H22, &H2F, &H64, &H69, &H7E, &H73, &H50, &H5D, &H4A, &H47, _&HDC, &HD1, &HC6, &HCB, &HE8, &HE5, &HF2, &HFF, &HB4, &HB9, &HAE, &HA3, &H80, &H8D, &H9A, &H97) g14 = Array( _&H0, &HE, &H1C, &H12, &H38, &H36, &H24, &H2A, &H70, &H7E, &H6C, &H62, &H48, &H46, &H54, &H5A, _&HE0, &HEE, &HFC, &HF2, &HD8, &HD6, &HC4, &HCA, &H90, &H9E, &H8C, &H82, &HA8, &HA6, &HB4, &HBA, _&HDB, &HD5, &HC7, &HC9, &HE3, &HED, &HFF, &HF1, &HAB, &HA5, &HB7, &HB9, &H93, &H9D, &H8F, &H81, _&H3B, &H35, &H27, &H29, &H3, &HD, &H1F, &H11, &H4B, &H45, &H57, &H59, &H73, &H7D, &H6F, &H61, _&HAD, &HA3, &HB1, &HBF, &H95, &H9B, &H89, &H87, &HDD, &HD3, &HC1, &HCF, &HE5, &HEB, &HF9, &HF7, _&H4D, &H43, &H51, &H5F, &H75, &H7B, &H69, &H67, &H3D, &H33, &H21, &H2F, &H5, &HB, &H19, &H17, _&H76, &H78, &H6A, &H64, &H4E, &H40, &H52, &H5C, &H6, &H8, &H1A, &H14, &H3E, &H30, &H22, &H2C, _&H96, &H98, &H8A, &H84, &HAE, &HA0, &HB2, &HBC, &HE6, &HE8, &HFA, &HF4, &HDE, &HD0, &HC2, &HCC, _&H41, &H4F, &H5D, &H53, &H79, &H77, &H65, &H6B, &H31, &H3F, &H2D, &H23, &H9, &H7, &H15, &H1B, _&HA1, &HAF, &HBD, &HB3, &H99, &H97, &H85, &H8B, &HD1, &HDF, &HCD, &HC3, &HE9, &HE7, &HF5, &HFB, _&H9A, &H94, &H86, &H88, &HA2, &HAC, &HBE, &HB0, &HEA, &HE4, &HF6, &HF8, &HD2, &HDC, &HCE, &HC0, _&H7A, &H74, &H66, &H68, &H42, &H4C, &H5E, &H50, &HA, &H4, &H16, &H18, &H32, &H3C, &H2E, &H20, _&HEC, &HE2, &HF0, &HFE, &HD4, &HDA, &HC8, &HC6, &H9C, &H92, &H80, &H8E, &HA4, &HAA, &HB8, &HB6, _&HC, &H2, &H10, &H1E, &H34, &H3A, &H28, &H26, &H7C, &H72, &H60, &H6E, &H44, &H4A, &H58, &H56, _&H37, &H39, &H2B, &H25, &HF, &H1, &H13, &H1D, &H47, &H49, &H5B, &H55, &H7F, &H71, &H63, &H6D, _&HD7, &HD9, &HCB, &HC5, &HEF, &HE1, &HF3, &HFD, &HA7, &HA9, &HBB, &HB5, &H9F, &H91, &H83, &H8D) sbox = Array( _&H63, &H7C, &H77, &H7B, &HF2, &H6B, &H6F, &HC5, &H30, &H1, &H67, &H2B, &HFE, &HD7, &HAB, &H76, _&HCA, &H82, &HC9, &H7D, &HFA, &H59, &H47, &HF0, &HAD, &HD4, &HA2, &HAF, &H9C, &HA4, &H72, &HC0, _&HB7, &HFD, &H93, &H26, &H36, &H3F, &HF7, &HCC, &H34, &HA5, &HE5, &HF1, &H71, &HD8, &H31, &H15, _&H4, &HC7, &H23, &HC3, &H18, &H96, &H5, &H9A, &H7, &H12, &H80, &HE2, &HEB, &H27, &HB2, &H75, _&H9, &H83, &H2C, &H1A, &H1B, &H6E, &H5A, &HA0, &H52, &H3B, &HD6, &HB3, &H29, &HE3, &H2F, &H84, _&H53, &HD1, &H0, &HED, &H20, &HFC, &HB1, &H5B, &H6A, &HCB, &HBE, &H39, &H4A, &H4C, &H58, &HCF, _&HD0, &HEF, &HAA, &HFB, &H43, &H4D, &H33, &H85, &H45, &HF9, &H2, &H7F, &H50, &H3C, &H9F, &HA8, _&H51, &HA3, &H40, &H8F, &H92, &H9D, &H38, &HF5, &HBC, &HB6, &HDA, &H21, &H10, &HFF, &HF3, &HD2, _&HCD, &HC, &H13, &HEC, &H5F, &H97, &H44, &H17, &HC4, &HA7, &H7E, &H3D, &H64, &H5D, &H19, &H73, _&H60, &H81, &H4F, &HDC, &H22, &H2A, &H90, &H88, &H46, &HEE, &HB8, &H14, &HDE, &H5E, &HB, &HDB, _&HE0, &H32, &H3A, &HA, &H49, &H6, &H24, &H5C, &HC2, &HD3, &HAC, &H62, &H91, &H95, &HE4, &H79, _&HE7, &HC8, &H37, &H6D, &H8D, &HD5, &H4E, &HA9, &H6C, &H56, &HF4, &HEA, &H65, &H7A, &HAE, &H8, _&HBA, &H78, &H25, &H2E, &H1C, &HA6, &HB4, &HC6, &HE8, &HDD, &H74, &H1F, &H4B, &HBD, &H8B, &H8A, _&H70, &H3E, &HB5, &H66, &H48, &H3, &HF6, &HE, &H61, &H35, &H57, &HB9, &H86, &HC1, &H1D, &H9E, _&HE1, &HF8, &H98, &H11, &H69, &HD9, &H8E, &H94, &H9B, &H1E, &H87, &HE9, &HCE, &H55, &H28, &HDF, _&H8C, &HA1, &H89, &HD, &HBF, &HE6, &H42, &H68, &H41, &H99, &H2D, &HF, &HB0, &H54, &HBB, &H16) sboxinv = Array( _&H52, &H9, &H6A, &HD5, &H30, &H36, &HA5, &H38, &HBF, &H40, &HA3, &H9E, &H81, &HF3, &HD7, &HFB, _&H7C, &HE3, &H39, &H82, &H9B, &H2F, &HFF, &H87, &H34, &H8E, &H43, &H44, &HC4, &HDE, &HE9, &HCB, _&H54, &H7B, &H94, &H32, &HA6, &HC2, &H23, &H3D, &HEE, &H4C, &H95, &HB, &H42, &HFA, &HC3, &H4E, _&H8, &H2E, &HA1, &H66, &H28, &HD9, &H24, &HB2, &H76, &H5B, &HA2, &H49, &H6D, &H8B, &HD1, &H25, _&H72, &HF8, &HF6, &H64, &H86, &H68, &H98, &H16, &HD4, &HA4, &H5C, &HCC, &H5D, &H65, &HB6, &H92, _&H6C, &H70, &H48, &H50, &HFD, &HED, &HB9, &HDA, &H5E, &H15, &H46, &H57, &HA7, &H8D, &H9D, &H84, _&H90, &HD8, &HAB, &H0, &H8C, &HBC, &HD3, &HA, &HF7, &HE4, &H58, &H5, &HB8, &HB3, &H45, &H6, _&HD0, &H2C, &H1E, &H8F, &HCA, &H3F, &HF, &H2, &HC1, &HAF, &HBD, &H3, &H1, &H13, &H8A, &H6B, _&H3A, &H91, &H11, &H41, &H4F, &H67, &HDC, &HEA, &H97, &HF2, &HCF, &HCE, &HF0, &HB4, &HE6, &H73, _&H96, &HAC, &H74, &H22, &HE7, &HAD, &H35, &H85, &HE2, &HF9, &H37, &HE8, &H1C, &H75, &HDF, &H6E, _&H47, &HF1, &H1A, &H71, &H1D, &H29, &HC5, &H89, &H6F, &HB7, &H62, &HE, &HAA, &H18, &HBE, &H1B, _&HFC, &H56, &H3E, &H4B, &HC6, &HD2, &H79, &H20, &H9A, &HDB, &HC0, &HFE, &H78, &HCD, &H5A, &HF4, _&H1F, &HDD, &HA8, &H33, &H88, &H7, &HC7, &H31, &HB1, &H12, &H10, &H59, &H27, &H80, &HEC, &H5F, _&H60, &H51, &H7F, &HA9, &H19, &HB5, &H4A, &HD, &H2D, &HE5, &H7A, &H9F, &H93, &HC9, &H9C, &HEF, _&HA0, &HE0, &H3B, &H4D, &HAE, &H2A, &HF5, &HB0, &HC8, &HEB, &HBB, &H3C, &H83, &H53, &H99, &H61, _&H17, &H2B, &H4, &H7E, &HBA, &H77, &HD6, &H26, &HE1, &H69, &H14, &H63, &H55, &H21, &HC, &H7D) rcon = Array( _&H8D, &H1, &H2, &H4, &H8, &H10, &H20, &H40, &H80, &H1B, &H36, &H6C, &HD8, &HAB, &H4D, &H9A, _&H2F, &H5E, &HBC, &H63, &HC6, &H97, &H35, &H6A, &HD4, &HB3, &H7D, &HFA, &HEF, &HC5, &H91, &H39, _&H72, &HE4, &HD3, &HBD, &H61, &HC2, &H9F, &H25, &H4A, &H94, &H33, &H66, &HCC, &H83, &H1D, &H3A, _&H74, &HE8, &HCB, &H8D, &H1, &H2, &H4, &H8, &H10, &H20, &H40, &H80, &H1B, &H36, &H6C, &HD8, _&HAB, &H4D, &H9A, &H2F, &H5E, &HBC, &H63, &HC6, &H97, &H35, &H6A, &HD4, &HB3, &H7D, &HFA, &HEF, _&HC5, &H91, &H39, &H72, &HE4, &HD3, &HBD, &H61, &HC2, &H9F, &H25, &H4A, &H94, &H33, &H66, &HCC, _&H83, &H1D, &H3A, &H74, &HE8, &HCB, &H8D, &H1, &H2, &H4, &H8, &H10, &H20, &H40, &H80, &H1B, _&H36, &H6C, &HD8, &HAB, &H4D, &H9A, &H2F, &H5E, &HBC, &H63, &HC6, &H97, &H35, &H6A, &HD4, &HB3, _&H7D, &HFA, &HEF, &HC5, &H91, &H39, &H72, &HE4, &HD3, &HBD, &H61, &HC2, &H9F, &H25, &H4A, &H94, _&H33, &H66, &HCC, &H83, &H1D, &H3A, &H74, &HE8, &HCB, &H8D, &H1, &H2, &H4, &H8, &H10, &H20, _&H40, &H80, &H1B, &H36, &H6C, &HD8, &HAB, &H4D, &H9A, &H2F, &H5E, &HBC, &H63, &HC6, &H97, &H35, _&H6A, &HD4, &HB3, &H7D, &HFA, &HEF, &HC5, &H91, &H39, &H72, &HE4, &HD3, &HBD, &H61, &HC2, &H9F, _&H25, &H4A, &H94, &H33, &H66, &HCC, &H83, &H1D, &H3A, &H74, &HE8, &HCB, &H8D, &H1, &H2, &H4, _&H8, &H10, &H20, &H40, &H80, &H1B, &H36, &H6C, &HD8, &HAB, &H4D, &H9A, &H2F, &H5E, &HBC, &H63, _&HC6, &H97, &H35, &H6A, &HD4, &HB3, &H7D, &HFA, &HEF, &HC5, &H91, &H39, &H72, &HE4, &HD3, &HBD, _&H61, &HC2, &H9F, &H25, &H4A, &H94, &H33, &H66, &HCC, &H83, &H1D, &H3A, &H74, &HE8, &HCB) Dim expandedKey, block(16), aesKey(32), i, j, isEncodeDim sPlain, sPass, sCipher, sTemp, nonce(16), priorCipher(16)Dim x, r, y, temp(4), intTemp For i = 0 To 15nonce(i) = 0Next For i = 0 To (Len(sPassin) - 1)aesKey(i) = Asc(Mid(sPassin, i + 1, 1))Next For i = Len(sPassin) To 31aesKey(i) = 0Next expandedKey = expandKey(aesKey, sbox, rcon) sPlain = sCountersCipher = ""j = 0 sTemp = Mid(sPlain, j * 16 + 1, 16) If Len(sTemp) < 16 ThenFor i = Len(sTemp) To 15sTemp = sTemp & Chr(0)NextEnd If For i = 0 To 15block(i) = Asc(Mid(sTemp, (i Mod 4) * 4 + (i \ 4) + 1, 1))Next j = j + 1r = 0For i = 0 To 15block(i) = block(i) Xor nonce(i) Xor expandedKey((i Mod 4) * 4 + (i \ 4))Next For x = 1 To 13block(0) = sbox(block(0))block(1) = sbox(block(1))block(2) = sbox(block(2))block(3) = sbox(block(3)) intTemp = sbox(block(4))block(4) = sbox(block(5))block(5) = sbox(block(6))block(6) = sbox(block(7))block(7) = intTemp intTemp = sbox(block(8))block(8) = sbox(block(10))block(10) = intTempintTemp = sbox(block(9))block(9) = sbox(block(11))block(11) = intTemp intTemp = sbox(block(12))block(12) = sbox(block(15))block(15) = sbox(block(14))block(14) = sbox(block(13))block(13) = intTemp r = x * 16For i = 0 To 3temp(0) = block(i)temp(1) = block(i + 4)temp(2) = block(i + 8)temp(3) = block(i + 12) block(i) = g2(temp(0)) Xor temp(3) Xor temp(2) Xor g3(temp(1)) Xor expandedKey(r + i * 4)block(i + 4) = g2(temp(1)) Xor temp(0) Xor temp(3) Xor g3(temp(2)) Xor expandedKey(r + i * 4 + 1)block(i + 8) = g2(temp(2)) Xor temp(1) Xor temp(0) Xor g3(temp(3)) Xor expandedKey(r + i * 4 + 2)block(i + 12) = g2(temp(3)) Xor temp(2) Xor temp(1) Xor g3(temp(0)) Xor expandedKey(r + i * 4 + 3)NextNext block(0) = sbox(block(0)) Xor expandedKey(224)block(1) = sbox(block(1)) Xor expandedKey(228)block(2) = sbox(block(2)) Xor expandedKey(232)block(3) = sbox(block(3)) Xor expandedKey(236) intTemp = sbox(block(4)) Xor expandedKey(237)block(4) = sbox(block(5)) Xor expandedKey(225)block(5) = sbox(block(6)) Xor expandedKey(229)block(6) = sbox(block(7)) Xor expandedKey(233)block(7) = intTemp intTemp = sbox(block(8)) Xor expandedKey(234)block(8) = sbox(block(10)) Xor expandedKey(226)block(10) = intTempintTemp = sbox(block(9)) Xor expandedKey(238)block(9) = sbox(block(11)) Xor expandedKey(230)block(11) = intTemp intTemp = sbox(block(12)) Xor expandedKey(231)block(12) = sbox(block(15)) Xor expandedKey(227)block(15) = sbox(block(14)) Xor expandedKey(239)block(14) = sbox(block(13)) Xor expandedKey(235)block(13) = intTemp For i = 0 To 15nonce(i) = block(i)Next For i = 0 To 15sCipher = sCipher & Chr(block((i Mod 4) * 4 + (i \ 4)))Next RunAES = sCipher
End Function
Function expandKey(ByRef key(), ByRef box(), ByRef rcon())'MOD added () to array variablesDim rConIter, temp(), i, result(240) ReDim temp(4)rConIter = 1 For i = 0 To 31result(i) = key(i)Next For i = 32 To 239 Step 4temp(0) = result(i - 4)temp(1) = result(i - 3)temp(2) = result(i - 2)temp(3) = result(i - 1) If i Mod 32 = 0 Thentemp = keyScheduleCore(temp, rConIter, box, rcon)rConIter = rConIter + 1End If If i Mod 32 = 16 Thentemp(0) = box(temp(0))temp(1) = box(temp(1))temp(2) = box(temp(2))temp(3) = box(temp(3))End If result(i) = result(i - 32) Xor temp(0)result(i + 1) = result(i - 31) Xor temp(1)result(i + 2) = result(i - 30) Xor temp(2)result(i + 3) = result(i - 29) Xor temp(3)Next expandKey = result
End Function
Function keyScheduleCore(ByRef row(), ByVal a, ByRef box(), ByRef rcon())Dim result(4), iFor i = 0 To 3result(i) = box(row((i + 5) Mod 4))Nextresult(0) = result(0) Xor rcon(a)keyScheduleCore = result
End Function 

From: https://bytes.com/topic/access/insights/964786-vba-rnd-function-bad-what-use-instead