--- She’s already been back to Wuxi, ________?

--- ________. She is on a visit to Shanghai.

A．isn’t she; No

B．hasn’t she; Yes

C．isn’t she; Yes

D．hasn’t she; No

在当前目录下有一个名为“myfile.txt”的文本文件，其中有若干行文本。下列程序的功能是读入此文件中的所有文本行，按行计算每行字符的ASCII码之和，并显示在窗体上。请填空。
Private Sub Command1_Click()
Dim ch$,ascii As Integer
Open"myfile.txt"For______AS#1
While NOt EOF(1)
Line Input#1.ch
ascii=toascii(______)
Print ascii
Wend
Close#1
End Sub
Private Function toascii(mystr$)As Integer
n=0
For k=1 To______
n=n+Asc(Mid(mystr,k,1))
Next k
toascii=n
End Function