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<TD align=left width=300><B>关键字:</B><BR>Effective C++ </TD>
<TD align=middle width=120><B>贴文时间</B><BR>2001-7-10 21:20:47 </TD>
<TD align=middle width=80><B>文章类型: </B><BR>翻译 </TD>
<TD align=middle width=100><B>给贴子投票 </B><BR><A
href="http://www.csdn.net/develop/addscore.asp?id=8786">投票</A> </TD></TR>
<TR>
<TD> lostmouse 翻译 </TD>
<TD vAlign=top colSpan=3><B>出处: </B><A
href="http://www.csdn.net/develop/article/8/Effective%20C++%202e%20e-book">Effective
C++ 2e e-book </A></TD></TR>
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<P>类和函数:设计与声明</P>
<P>在程序中声明一个新类将导致产生一种新的类型:类的设计就是类型设计。可能你对类型设计没有太多经验,因为大多数语言没有为你提供实践的机会。在C++中,这却是很基本的特性,不是因为你想去做才可以这么做,而是因为每次你声明一个类的时候实际上就在做,无论你想不想做。</P>
<P>设计一个好的类很具有挑战性,因为设计好的类型很具有挑战性。好的类型具有自然的语法,直观的语义和高效的实现。在C++中,一个糟糕的类的定义是无法实现这些目标的。即使一个类的成员函数的性能也是由这些成员函数的声明和定义决定的。</P>
<P>那么,怎么着手设计高效的类呢?首先,必须清楚你面临的问题。实际上,设计每个类时都会遇到下面的问题,它的答案将影响到你的设计。</P>
<P>·对象将如何被创建和摧毁?它将极大地影响构造函数和析构函数的设计,以及自定义的operator new, operator new[], operator
delete, 和operator delete[]。(条款M8描述了这些术语的区别)</P>
<P>·对象初始化和对象赋值有什么不同?答案决定了构造函数和赋值运算符的行为以及它们之间的区别。</P>
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