csdn_文档中心_c++中的内部连接与外部连接(一).htm

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            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>c)enum</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">定义</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>d)inline</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">函数定义</SPAN><SPAN 
            lang=EN-US>(</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">包括自由函数和非自由函数</SPAN><SPAN 
            lang=EN-US>)</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>e)</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">类的定义</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>f)</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">名字空间中</SPAN><SPAN 
            lang=EN-US>const</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">常量定义</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>g)union</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的定义</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><SPAN style="mso-tab-count: 1"><FONT 
            size=3>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
</FONT></SPAN></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN></SPAN><B><I><SPAN 
            style="FONT-FAMILY: 宋体; FONT-SIZE: 12pt; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">外部连接</SPAN></I></B><SPAN 
            lang=EN-US>:</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">在一个多文件程序中，如果一个名称在连接时可以和其它编译单元交互，那么这个名称就有外部连接。</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN></SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">以下情况有外部连接</SPAN><SPAN 
            lang=EN-US>:</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>a)</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">类非</SPAN><SPAN 
            lang=EN-US>inline</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">函数总有外部连接。包括类成员函数和类静态成员函数</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>b)</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">类静态成员变量总有外部连接。</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>c)</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">名字空间</SPAN><SPAN 
            lang=EN-US>(</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">包括全局名字空间</SPAN><SPAN 
            lang=EN-US>)</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">中非静态自由函数、非静态友元函数及非静态变量</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><SPAN style="mso-tab-count: 1"><FONT 
            size=3>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
</FONT></SPAN></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN></SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">下面举例说明：</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><B>a)</B></SPAN><B><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">声明、</SPAN><SPAN 
            lang=EN-US>enum</SPAN></B><B><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">定义、</SPAN><SPAN 
            lang=EN-US>union</SPAN></B><B><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">定义有内部连接</SPAN><SPAN 
            lang=EN-US><o:p></o:p></SPAN></B></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt 45pt"><FONT 
            size=3><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">所有的声明、</SPAN><SPAN 
            lang=EN-US>enum</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">定义及</SPAN><SPAN 
            lang=EN-US>union</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">定义在编译后不会产生连接符号，也就是在不同编译单元中有相同名称的声明及</SPAN><SPAN 
            lang=EN-US>enum</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">、</SPAN><SPAN 
            lang=EN-US>union</SPAN><SPAN 
            style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">定义并不会在连接时发生发现多个符号的错误。</SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN 
            lang=EN-US><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><SPAN style="COLOR: green">// 
            main.cpp<o:p></o:p></SPAN></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US style="COLOR: green"><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>typedef int Int;<SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>//typedef </SPAN><SPAN 
            style="COLOR: green; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">声明，内部连接</SPAN><SPAN 
            lang=EN-US style="COLOR: green"><o:p></o:p></SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US style="COLOR: green"><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>enum Color{red};<SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp; </SPAN><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>//enum</SPAN><SPAN 
            style="COLOR: green; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">定义</SPAN><SPAN 
            lang=EN-US style="COLOR: green">,</SPAN><SPAN 
            style="COLOR: green; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">内部连接</SPAN><SPAN 
            lang=EN-US style="COLOR: green"><o:p></o:p></SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><FONT size=3><SPAN 
            lang=EN-US style="COLOR: green"><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>union X<SPAN 
            style="mso-tab-count: 3">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>//union</SPAN><SPAN 
            style="COLOR: green; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">定义，内部连接</SPAN><SPAN 
            lang=EN-US style="COLOR: green"><o:p></o:p></SPAN></FONT></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>{<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>long a;<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>char b[10];<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>};<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>int main(void)<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>{<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>Int i = red;<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><SPAN 
            style="mso-tab-count: 1">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>return i;<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN>}<o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN 
            style="mso-tab-count: 2">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 
            </SPAN><o:p></o:p></FONT></SPAN></P>
            <P class=MsoNormal style="MARGIN: 0cm 0cm 0pt"><SPAN lang=EN-US 
            style="COLOR: green"><FONT size=3><SPAN