下列说法正确的是( )
Private Sub Command1_Click ()
Dim i As Integer, n As Integer, flag As Boolean, txt As String
txt=Text1. Text
n=Len(txt)
c=1
For i=1 To n-1
If Mid (txt, i,1)= ① Then
flag=True
c=c+1
Else
flag=Fals
End If
If ② Then
List1. AddItem Mid (txt, i-c+1, c)
c=1
End If
Next i
End sub
① ②