31.有一个分段函数,当X<0时,Y=-1;当X=0时,Y=0;当X>0时,Y=1。该分段函数在程序段中可表达为: A、If X<0 Then Y=-1 If X=0 Then Y=0 Else Y=1 B、If X>0 Then Y=1 If X=0 Then Y=0 Else Y=-1 C、If X<0 Then Y=-1 ElseIf X=0 Then Y=0 Else Y=1 D、If X<0 Then Y=-1 ElseIf X=0 Then Y=0 Else Y=1
A B C D
32.在窗体上画一个名称为Command1的命令按钮,然后编写如下事件过程:
Private Sub Command1_Click() a = "ABBACKDIEKEI" For I = 9 To 2 Step -3 x = Mid(a, I, I) y = Left(a, I) z = Right(a, I) z = x & y & z Next I Print z End Sub