VB.NET 使用 ListBox 存入隨機且不重覆的資料

Option Explicit

Dim RndSeedS As String

Private Sub CMD_Proc_Click()

Dim RndN As Long, Ct As Long, i As Long, k1 As Long, k2 As Long
Dim tempS As String

Dim LastTimer As Double

LastTimer = Timer

'------- Ini. Var. & Obj. -------
Ct = Val(TB1.Text)
 If Ct <= 0 Then Exit Sub

LB1.Clear

'------- Ini. Randomized Seed --------
RndSeedS = "/"
For i = 1 To Ct
  RndSeedS = RndSeedS & i & "/"
Next i

'------ Start Proc. > Select Rnd Num In RndSeedS Then Delete -------

Do
  RndN = Fix((Ct) * Rnd + 1) 'Find Pos. of Slash
  k1 = UserInstr(RndN) '/x/  < 1st slash
  k2 = InStr(k1 + 1, RndSeedS, "/") '/x/   < 2nd slash
  
    tempS = Mid(RndSeedS, k1 + 1, k2 - k1 - 1)
    RndSeedS = Left(RndSeedS, k1) & Right(RndSeedS, Len(RndSeedS) - k2)
    
      LB1.AddItem tempS
  
  Ct = Ct - 1
Loop While Ct <> 0

'-------- Show The Time ------
LastTimer = Timer - LastTimer
'Label_C(1).Caption = "Time : " & Format(LastTimer, "0.0000") & " s"


End Sub

Public Function UserInstr(ByVal Ti As Long) As Long 'Find String (Instr) In RndSeedS Continuously

Dim m As Long

m = 0
Do
  
  Ti = Ti - 1
  
  m = InStr(m + 1, RndSeedS, "/")
  If m = 0 Then UserInstr = Len(RndSeedS): Exit Function
  If Ti = 0 Then UserInstr = m: Exit Function
Loop

End Function