推荐 如果变量a中保存字母"m"，则以下程序段执行后，变量Str$的值是 Select Case a$ Case "A" To "Z" Str$ = "Upper Case" Case "0" To "9" Str$ = "Number " Case "!", "?", ",", ") ", ";" Str$ = "Punctuaton" Case "" Str$ = "Null String" Case Is < 32 Str$ = "Special Character" Case Else Str$ = "Unknown Character" End Select 以下叙述中正确的是 有如下程序：Private Sub Command1_Click() Dim i As Integer， j As Integer Dim sum As Integer n＝1 Do j＝1 Do sum＝sum＋j j＝j＋1 Print j； Loop Until j>3 n＝n＋2 Loop Until n>10 Print sumEnd Sub运行上述程序，外层Do循环执行的次数为( )。 命令？ LEN(SPACE(3)－SPACE(2))的结果是( )。 下列关于面向对象数据库系统的复杂对象的叙述中，哪一条是错误的？