I need a less lagging Kill Duplicates in List

[Aaron Young]

The LB_FINDSTRINGEXACT Message used with the SendMessage API will quickly tell you if an Item is already in the List, ie.

Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal hwnd As Long, ByVal wMsg As Long, ByVal wParam As Long, lParam As Any) As Long
Private Const LB_FINDSTRINGEXACT = &H1A2

Private Sub Command1_Click()
    'Clear the List and Start the Timer
    List1.Clear
    Timer1.Interval = 100
End Sub

Private Sub Timer1_Timer()
    'Generate a Number Between 0 And 9
    Dim sChar As String
    sChar = Chr(Int(Rnd * 10) + 48)
    'Only Add it to the List if it's not already there.
    If SendMessage(List1.hwnd, LB_FINDSTRINGEXACT, -1, ByVal sChar) < 0 Then
        List1.AddItem sChar
    End If
End Sub