单项选择题
设有如下通用过程: Public Function Fun(xStr As String)As String Dim tSt]r As String.strL As Integer tStr="" strL=Len(xStr)i=1 Do While i<=strL/2 tStr=tStr&Mid(xStr,i,1)&Mid(xStr,strL-i+1,1) i=i+1 Loop Fun=tStr End Function 在窗体上画一个名称为Command1的命令按钮。然后编写如下的事件过程: Private Sub Commandl_Click() Dim S1 As String S1=”abcdef”:Print UCase(Fun(S1)) End Sub 程序运行后,单击命令按钮,输出结果是
A.ABCDEF
B.abcdef
C.AFBECD
D.DEFABC