VBBase64编码类代码计算机等级考试

文章作者 100test 发表时间 2010:01:01 10:53:03
来源 100Test.Com百考试题网

　　Attribute VB_Name = "ModBase64"
　　Option Explicit
　　Public key(1 To 3) As Long
　　Private Const base64 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789 /"
　　Public Sub GenKey()Sub GenKey()
　　Dim d As Long, phi As Long, e As Long
　　Dim m As Long, x As Long, q As Long
　　Dim p As Long
　　Randomize
　　On Error GoTo top
　　top:
　　p = Rnd * 1000 1
　　If IsPrime(p) = False Then GoTo top
　　Sel_q:
　　q = Rnd * 1000 1
　　If IsPrime(q) = False Then GoTo Sel_q
　　n = p * q 1
　　phi = (p - 1) * (q - 1) 1
　　d = Rnd * n 1
　　If d = 0 Or n = 0 Or d = 1 Then GoTo top
　　e = Euler(phi, d)
　　If e = 0 Or e = 1 Then GoTo top
　　x = Mult(255, e, n)
　　If Not Mult(x, d, n) = 255 Then
　　DoEvents
　　GoTo top
　　ElseIf Mult(x, d, n) = 255 Then
　　key(1) = e
　　key(2) = d
　　key(3) = n
　　End If
　　End Sub
　　Public Function Euler()Function Euler(ByVal a As Long, ByVal b As Long) As Long
　　On Error GoTo error2
　　r1 = a: r = b
　　p1 = 0: p = 1
　　q1 = 2: q = 0
　　n = -1
　　Do Until r = 0
　　r2 = r1: r1 = r
　　p2 = p1: p1 = p
　　q2 = q1: q1 = q
　　n = n 1
　　r = r2 Mod r1
　　c = r2 r1
　　p = (c * p1) p2
　　q = (c * q1) q2
　　Loop
　　s = (b * p1) - (a * q1)
　　If s