用DEFINE CLASS命令定义一个Myform类时，要想为该类添加一个按钮对象，应当使用的基本代码是( )
A．Addobject("commandl"，"commandbutton")
B．Myform．Addobject("commandl"，"commandbutton")
C．AddObjectMyform．Commandl AS commandbutton
D．Add Object Commandl AS commandbutton

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