You could do this:
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 WM_SETTEXT = &HC
Private Sub Form_Load()
Dim s As String
s = String(70000, "@")
SendMessage text1.hwnd, WM_SETTEXT, 0&, ByVal s
End Sub
"Two strings walk into a bar. The first string says to the bartender: 'Bartender, I'll have a beer. u.5n$x5t?*&4ru!2[sACC~ErJ'. The second string says: 'Pardon my friend, he isn't NULL terminated'."