📄 csdn_文档中心_新的c语言：一切都源于fortran.htm
字号:
lang=EN-US>Y</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">，文中意思是</SPAN><SPAN
lang=EN-US>Y</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">是实参数，而下面程序出现的</SPAN><SPAN
lang=EN-US>X</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">是形参数，只是属于函数</SPAN><SPAN
lang=EN-US>F</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的内部变量，但是当把</SPAN><SPAN
lang=EN-US>Y</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">复制给</SPAN><SPAN
lang=EN-US>X</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">后，并且改变</SPAN><SPAN
lang=EN-US>X</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">同时将改变外面调用的</SPAN><SPAN
lang=EN-US>Y</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的值</SPAN><SPAN
lang=EN-US>]</SPAN></P>
<P class=MsoNormal
style="TEXT-INDENT: 31.5pt; mso-char-indent-count: 3.0; mso-char-indent-size: 10.5pt"><I><SPAN
lang=EN-US>Example 1:</SPAN></I><SPAN lang=EN-US
style="mso-font-kerning: 0pt"><o:p></o:p></SPAN></P><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>SUBROUTINE F(X)</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>INTEGER X</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>X = 6</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>END</SPAN></PRE>
<P class=MsoNormal style="TEXT-INDENT: 21pt"><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">这样的参数传递方式就使争论随之而来。不同的</SPAN><SPAN
lang=EN-US>FORTRAN</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">编译器可以选择两种实现方式中的一种来获得</SPAN><SPAN
lang=EN-US>FORTRAN</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">中的参数传递语义。第一种方式是引用参数传递（</SPAN><SPAN
lang=EN-US>by reference</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">），也就是典型的</SPAN><SPAN
lang=EN-US>C</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">程序员所使用的：写一个函数，并且在它的调用者中修改变量。（</SPAN><SPAN
lang=EN-US>write a function that modifies a variable in its
caller</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">）。传递给函数的是一个参数的地址，并且在需要的时候任何地方都可以间接访问这个参数。如果</SPAN><SPAN
lang=EN-US>FORTRAN</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">编译器产生</SPAN><SPAN
lang=EN-US>C</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">代码的话，就会和下面</SPAN><SPAN
lang=EN-US>Example 2.</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的</SPAN><SPAN
lang=EN-US>C</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">代码类似。</SPAN></P>
<P class=MsoNormal
style="TEXT-INDENT: 31.5pt; mso-char-indent-count: 3.0; mso-char-indent-size: 10.5pt"><I><SPAN
lang=EN-US>Example 2:</SPAN></I><SPAN lang=EN-US
style="mso-font-kerning: 0pt"><o:p></o:p></SPAN></P><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>void f(int *x)</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>{</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>*x = 6;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>}</SPAN></PRE>
<P class=MsoNormal style="TEXT-INDENT: 21pt"><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">然而，对于一些类型的计算机来说，间接访问局部变量比直接引用访问所带来的运行时开销要大的多。这也就导致了</SPAN><SPAN
lang=EN-US>FORTRAN</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">中参数传递的第二种实现方式。实参的地址依然会被传递给函数，但是函数一旦被调用，就将生成一个实参数的局部拷贝</SPAN><SPAN
lang=EN-US>[</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">译注：传递的是地址，但是函数内部拷贝的却是参数值</SPAN><SPAN
lang=EN-US>]</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">，在函数生存期中将一直使用这个拷贝的局部变量，当函数返回时，将把拷贝变量赋值给调用函数的参数变量。这样的</SPAN><SPAN
lang=EN-US>FORTRAN</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">编译器如果产生</SPAN><SPAN
lang=EN-US>C</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">代码将会和下面的</SPAN><SPAN
lang=EN-US>Example 3</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">相类似。进</SPAN><SPAN
lang=EN-US>/</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">出拷贝（</SPAN><SPAN
lang=EN-US>copy in/copy out</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">）参数传递方式增加了函数进入和返回时的负担，但是如果一个参数被多次引用，而间接引用（在一些机器上代价十分昂贵）却不再使用的话，导致的结果就是性能的提升（在一些机器上面而言）。</SPAN><SPAN
lang=EN-US>[</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">译注：就是说第一种方式的主要的调用开销是间接引用，第二种方式的主要调用开销是拷贝变量，其中哪种更好，需要根据真实代码的情况衡量决定</SPAN><SPAN
lang=EN-US>]</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">。</SPAN></P>
<P class=MsoNormal
style="TEXT-INDENT: 31.5pt; mso-char-indent-count: 3.0; mso-char-indent-size: 10.5pt"><I><SPAN
lang=EN-US>Example 3:</SPAN></I><SPAN lang=EN-US
style="mso-font-kerning: 0pt"><o:p></o:p></SPAN></P><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>void f(int *x)</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>{</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>int xcopy = *x;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>xcopy = 6;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>*x = xcopy;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>}</SPAN></PRE>
<P class=MsoNormal style="TEXT-INDENT: 21pt"><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">大多数时候，编译器如何实现语言特征通常都被认为不过只是“实现细节”。它们不会影响程序员编写程序的方式，而语言的标准委员会允许语言的实现者自由选择和改变实现方式。然而，根据使用的参数传递机制，</SPAN><SPAN
lang=EN-US>FORTRAN</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">程序会产生不同的结果。考虑下面</SPAN><SPAN
lang=EN-US>Example 4</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">中的</SPAN><SPAN
lang=EN-US>FORTRAN</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">代码，以及以两种方式转换成的</SPAN><SPAN
lang=EN-US>C</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">代码：</SPAN></P>
<P class=MsoNormal
style="TEXT-INDENT: 31.5pt; mso-char-indent-count: 3.0; mso-char-indent-size: 10.5pt"><I><SPAN
lang=EN-US>Example 4:</SPAN></I><SPAN lang=EN-US
style="mso-font-kerning: 0pt"><o:p></o:p></SPAN></P><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>SUBROUTINE G(X, Y)</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>INTEGER X, Y</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>X = 1 + X</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>Y = 5 + Y</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>END</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US> <o:p></o:p></SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>// Translation using "by reference"</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>void g(int *x, int *y)</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>{</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>*x = 1 + *x;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>*y = 5 + *y;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>}</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US> <o:p></o:p></SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>// Translation using</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>// "copy in/copy out"</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>void g(int *x, int *y)</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>{</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>int xcopy = *x;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>int ycopy = *y;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>xcopy = 1 + xcopy;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>ycopy = 5 + ycopy;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>*x = xcopy;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US><SPAN style="mso-spacerun: yes"> </SPAN>*y = ycopy;</SPAN></PRE><PRE style="MARGIN: 0cm 36pt 0pt"><SPAN lang=EN-US>}</SPAN></PRE>
<P class=MsoNormal style="TEXT-INDENT: 21pt"><SPAN
lang=EN-US>G</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">函数给它的参数加上了不同的常量，如果你把参数</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">和</SPAN><SPAN
lang=EN-US>B</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">传递给函数</SPAN><SPAN
lang=EN-US>G</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">，并且在调用前</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的值是</SPAN><SPAN
lang=EN-US>1</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">，</SPAN><SPAN
lang=EN-US>B</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的值是</SPAN><SPAN
lang=EN-US>10</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">。不用怀疑，无论使用</SPAN><SPAN
lang=EN-US>FORTRAN</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">中的那种函数参数传递机制，当函数返回时</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的值将变成</SPAN><SPAN
lang=EN-US>2</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">而</SPAN><SPAN
lang=EN-US>B</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的值将变成</SPAN><SPAN
lang=EN-US>15</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">。但是请考虑，如果你传递参数都是的</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">（并且被初始化为</SPAN><SPAN
lang=EN-US>1</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">），将会是什么情况？如果是使用引用调用（</SPAN><SPAN
lang=EN-US>by reference</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">）的参数传递机制，在函数返回时</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">将的值将变成</SPAN><SPAN
lang=EN-US>7</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">。</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的值在赋值给</SPAN><SPAN
lang=EN-US>*x</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的过程中时候被更新，因为</SPAN><SPAN
lang=EN-US>x</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">和</SPAN><SPAN
lang=EN-US>y</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">都指向</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">，所以在随后的对</SPAN><SPAN
lang=EN-US>*y</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">赋值的过程中</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的值将再次被改写。相反，如果是使用进</SPAN><SPAN
lang=EN-US>/</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">出拷贝（</SPAN><SPAN
lang=EN-US>copy in/copy out</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">）的参数传递机制，在函数返回时，</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的值将是</SPAN><SPAN
lang=EN-US>6</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">。调用发生后，在函数</SPAN><SPAN
lang=EN-US>G</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">中将不同的拷贝变量，并且每一个都将在函数返回时赋值给</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">，但最后的一个拷贝变量的返回值才会成为</SPAN><SPAN
lang=EN-US>A</SPAN><SPAN
style="FONT-FAMILY: 宋体; mso-hansi-font-family: 'Times New Roman'; mso-ascii-font-family: 'Times New Roman'">的终值。</SPAN></P>
<P class=MsoNormal style="TEXT-INDENT: 21pt"><SPAN
lang=EN-US> <o:p></o:p></SPAN></P>
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -