单项选择题

在窗体上画一个命令按钮和一个文本框,并将窗体的KeyPreview属性设置为True,然后编写如下代码:
Dim SaveAll As String
Private Sub Form_Load()
Show
Text1.Text=" "
Text1.SetFocus
End Sub
Private Sub Command1_Click()
Text1.Text = Ucase(SaveAll)
End Sub
Private Sub Form_KeyPress(KeyAscii As Integer)
SaveAll=SaveAll+Chr(KeyAscii)
End Sub
程序运行后,在键盘上输入abcdefg,单击命令按钮,则文本框中显示的内容为

A.abcdefg
B.不显示任何信息
C.ABCDEFG
D.出错