book_text8.htm

深入编程内幕vc++ 非常适合处学者学习

            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">CArchive</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">的归档对象充当磁盘文件与程序中的对象的中介。归档对象总是与一个</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">CFile</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">对象相关联，从中获得一些进行序列化所需要的信息，比如说文件名，以及存取标志等。对象的持续化的主要工作就是将自己的成员变量或者当前状态保存起来。我们可以使用经过重载的流入和流出操作符直接向归档对象中保存或者取出变量成员的值，而将这些数据保存到磁盘文件中的工作由</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">CArchive</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">对象指示</SPAN><SPAN 
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            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">CFile</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">对象来完成。当用户在打开或保存拥有文档对象数据的文件或者使用文档对象的</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">Open 
            </SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、<SPAN 
            lang=EN-US><O:P> </O:P></SPAN></SPAN></P>
            <P class=MsoNormal 
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            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">Save<SPAN 
            style="mso-spacerun: yes">&nbsp; </SPAN>As</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">菜单命令时，</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">MFC</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">便会自动调用</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">Serialize</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">函数。</SPAN><SPAN 
            lang=EN-US 
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            </O:P></SPAN></P>
            <P class=MsoNormal 
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            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">使类实现序列化，需要五个步骤：</SPAN><SPAN 
            lang=EN-US 
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            </O:P></SPAN></P>
            <P class=MsoNormal 
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            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">1</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、从</SPAN><SPAN 
            lang=EN-US 
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            </SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">类或其派生类派生用户类</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">；</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt"><O:P> 
            </O:P></SPAN></P>
            <P class=MsoNormal 
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            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">2</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、在类声明中使用</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">DECLARE_SERIAL</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">宏；</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt"><O:P> 
            </O:P></SPAN></P>
            <P class=MsoNormal 
            style="WORD-BREAK: break-all; mso-line-height-alt: 1.3pt; punctuation-wrap: simple"><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">3</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、重载</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">Serialize 
            </SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">函数；</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt"><O:P> 
            </O:P></SPAN></P>
            <P class=MsoNormal 
            style="WORD-BREAK: break-all; mso-line-height-alt: 1.3pt; punctuation-wrap: simple"><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">4</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、定义不用变量的构造函数；<SPAN 
            lang=EN-US><O:P> </O:P></SPAN></SPAN></P>
            <P class=MsoNormal 
            style="WORD-BREAK: break-all; mso-line-height-alt: 1.3pt; punctuation-wrap: simple"><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">5</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">、在类实现文件中使用宏</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt">IMPLEMENT_SERIAL</SPAN><SPAN 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">。</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt"><O:P> 
            </O:P></SPAN></P>
            <P class=MsoNormal 
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            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">在下一节中，我们将以一个具体的实例来详细说明如何实现类的序列化。</SPAN><SPAN 
            lang=EN-US 
            style="FONT-SIZE: 10.5pt; mso-bidi-font-size: 10.0pt"><O:P> 
            </O:P></SPAN></P><SPAN lang=EN-US 
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            style="FONT-SIZE: 14pt; FONT-FAMILY: 黑体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'"><O:P> 
            </O:P></SPAN></P>
            <H3 style="mso-line-height-alt: 1.3pt"><A name=_Toc419881639><SPAN 
            lang=EN-US 
            style="FONT-FAMILY: 宋体; mso-hansi-font-family: MS Sans Serif; mso-bookmark: _Toc419740457">3．2 
            实例分析</SPAN></A></H3>
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            style="mso-ignore: vglayout" clear=all><SPAN lang=EN-US 
            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">在描述了类序列化的基本原理之后，让我们来看一个具体的序列化实例DrawLine。启动这个实例。<O:P> 
            </O:P></SPAN>
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            style="FONT-SIZE: 10.5pt; FONT-FAMILY: 宋体; mso-bidi-font-size: 10.0pt; mso-hansi-font-family: 'MS Sans Serif'">图<SPAN 
            lang=EN-US>3.9<O:P> </O:P></SPAN></SPAN></P>
            <P class=MsoBodyTextIndent3 
            style="mso-line-height-alt: 1.3pt">在这个实例中，我们将完成对直线的简单绘制。在视图按下鼠标左键，然后拖动鼠标到一个新位置松开鼠标，程序就画出一条直线。再来看看这个程序的基本构成。</P>
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