PHP编码风格指南 (PHP-FIG PSR-2)

本指南是 PSR-1 基本编码标准 的扩展。

本指罗列了通用的PHP代码格式规则和建议，意在减少不同作者的编码风格差异带来的认知障碍。

这里的风格约定衍生自若干成员项目。指南作者们在多个项目中协作，推动了这些指导条款落地。 指南的关键在于共享，而不是规则本身。

文中涉及的关键词 “MUST 必须”, “MUST NOT 必须不”, “REQUIRED 必需”, “SHALL 会”, “SHALL NOT 不会”, “SHOULD 应该”, “SHOULD NOT 不应该”, “RECOMMENDED 推荐的”, “MAY 可能”, 和 “OPTIONAL 可选的” 在RFC 2119 中有具体描述.

概览

1. 代码必需遵循 “基础编码标准” PSR [PSR-1]。
2. 代码缩进必须使用 4 空格，而不是tab。
3. 行长度必须无硬性限制; 软性限制必须为120字符；应该少于等于80字。
4. namespace声明后必须有一个空行，use声明后也必须有一个空行。
5. 类的｛ 必须在类名的下一行, ｝必须在body的下一行。
6. 方法的 { 必须在方法签名的下一行，} 必须在body的下一行。
7. 所有的属性和方法都要设置可见性； abstract和 final必须在可见性之前声明；static 必须在可见性后声明。
8. 结构控制关键词后必须有一个空格； 方法和函数必须没有空格。
9. 结构控制的 { 必须在同一行，} 必须在body的下一行。
10. 结构控制的 ( 后必须有空格， 结构控制的 ) 前必须没有空格。

例子

下面是一个综合的例子，可以帮助你对规则有一个概略的认识。

<code><span><?php </span><span>namespace</span><span>Vendor</span>\<span>Package</span>;

<span>use</span><span>FooInterface</span>;
<span>use</span><span>BarClass</span><span>as</span><span>Bar</span>;
<span>use</span><span>OtherVendor</span>\<span>OtherPackage</span>\<span>BazClass</span>;

<span><span>class</span><span>Foo</span><span>extends</span><span>Bar</span><span>implements</span><span>FooInterface</span>
{</span><span>public</span><span><span>function</span><span>sampleFunction</span><span>(<span>$a</span>, <span>$b</span> = null)</span>
    {</span><span>if</span> (<span>$a</span> === <span>$b</span>) {
            bar();
        } <span>elseif</span> (<span>$a</span> > <span>$b</span>) {
            <span>$foo</span>->bar(<span>$arg1</span>);
        } <span>else</span> {
            BazClass::bar(<span>$arg2</span>, <span>$arg3</span>);
        }
    }

    <span>final</span><span>public</span><span>static</span><span><span>function</span><span>bar</span><span>()</span>
    {</span><span>// 方法 body</span>
    }
}</span></code>

基本规则

基本编码标准

代码必须遵循PSR-1的条款。

文件

1. 所有文件必须使用 Unix LF (linefeed) 换行。
2. 所有PHP文件必须使用单个空行结束。
3. 只包含PHP的代码必须忽略php结束标记 ? >。

行

1. 行长度必须没有硬性限制。
2. 长度的软性限制必须为120字符；自动代码风格检查必须将120字设置为警告，必须不能设置为错误。
3. 行不应该超过80字符；超过这个长度的行应该切分为多个不超过80字符的行。
4. 非空行的结束必须没有尾随空格。
5. 为增强可读性，可增加空行来标志代码的关联性。
6. 每行包含的语句必须不能超过1条。

缩进

1. 代码必须使用 4 空格的缩进, 必须不用tab作为缩进。

注意：只使用空格，不用tab，有助于避免diffs,patches, history和annotations的问题。使用空格也有助于对齐。

关键词（保留字） 和 true/false/null

1. PHP保留字必须小写.
2. PHP常量 true, false和 null 必须小写.

Namespace 和 Use 声明

1. namespace 声明之后必须有空行。
2. 所有use 声明，必须在namespace声明之后。
3. 每个声明必须单独使用一个use。
4. use声明区之后必须有一个空行。

例如:

<code><span><?php </span><span>namespace</span><span>Vendor</span>\<span>Package</span>;

<span>use</span><span>FooClass</span>;
<span>use</span><span>BarClass</span><span>as</span><span>Bar</span>;
<span>use</span><span>OtherVendor</span>\<span>OtherPackage</span>\<span>BazClass</span>;

<span>// ... additional PHP code ...</span></span></code>

类, 属性 和 方法

这里的“类”包括 class、interface 和 trait。

继承 和 实现

extends 和 implements 关键字必须和类名在同一行声明。

类的 { 必须独占一行； } 必须在body的下一行。

<code><span><?php </span><span>namespace</span><span>Vendor</span>\<span>Package</span>;

<span>use</span><span>FooClass</span>;
<span>use</span><span>BarClass</span><span>as</span><span>Bar</span>;
<span>use</span><span>OtherVendor</span>\<span>OtherPackage</span>\<span>BazClass</span>;

<span><span>class</span><span>ClassName</span><span>extends</span><span>ParentClass</span><span>implements</span> \<span>ArrayAccess</span>, \<span>Countable</span>
{</span><span>// constants, properties, methods</span>
}</span></code>

implements 多个接口时，接口列表可以被分到多行，每个子行有一个缩进。如果这么做，第一个接口必须在implements 下一行，每行只能有一个接口。

<code><span><?php </span><span>namespace</span><span>Vendor</span>\<span>Package</span>;

<span>use</span><span>FooClass</span>;
<span>use</span><span>BarClass</span><span>as</span><span>Bar</span>;
<span>use</span><span>OtherVendor</span>\<span>OtherPackage</span>\<span>BazClass</span>;

<span><span>class</span><span>ClassName</span><span>extends</span><span>ParentClass</span><span>implements</span>
    \<span>ArrayAccess</span>,
    \<span>Countable</span>,
    \<span>Serializable</span>
{</span><span>// constants, properties, methods</span>
}</span></code>

属性

所有属性都必须声明 visibility（可见性）。

Var 关键字必须不能用于声明属性。

每行必须只声明一个属性。

不应该通过前缀下划线来标示protected和private的属性。

例：

<code><span><?php </span><span>namespace</span><span>Vendor</span>\<span>Package</span>;

<span><span>class</span><span>ClassName</span>
{</span><span>public</span><span>$foo</span> = <span>null</span>;
}</span></code>

方法

所有方法都必须声明可见性。

不应该通过前缀下划线来标示protected和private的方法。

声明方法时，方法名的后必须没有空格。 { 必须在同一行， } 必须在body的下一行。 (后必须没有空格，) 前必须没有空格。

一个方法声明的例子如下，注意 小括号,逗号,空格 和 花括号 的位置：

<code><span><?php </span><span>namespace</span><span>Vendor</span>\<span>Package</span>;

<span><span>class</span><span>ClassName</span>
{</span><span>public</span><span><span>function</span><span>fooBarBaz</span><span>(<span>$arg1</span>, &<span>$arg2</span>, <span>$arg3</span> = [])</span>
    {</span><span>// method body</span>
    }
}</span></code>

方法参数

方法的形参列表中, 每个逗号前必须没有空格。有默认值的参数必须在参数列表的最后。

<code><span><?php </span><span>namespace</span><span>Vendor</span>\<span>Package</span>;

<span><span>class</span><span>ClassName</span>
{</span><span>public</span><span><span>function</span><span>foo</span><span>(<span>$arg1</span>, &<span>$arg2</span>, <span>$arg3</span> = [])</span>
    {</span><span>// method body</span>
    }
}</span></code>

参数列表可以切分为多行，每个子行要有一个缩进。如果这么做，第一个参数必须独占一行，每行只能有一个参数。

参数列表切分为多行时，右括号)和左花括号{必须在同一行，之前必须有一个空格。

<code><span><?php </span><span>namespace</span><span>Vendor</span>\<span>Package</span>;

<span><span>class</span><span>ClassName</span>
{</span><span>public</span><span><span>function</span><span>aVeryLongMethodName</span><span>(
        ClassTypeHint <span>$arg1</span>,
        &<span>$arg2</span>,
        array <span>$arg3</span> = []
    )</span> {</span><span>// method body</span>
    }
}</span></code>

abstract, final 和 static

abstract和final声明必须在可见性之前声明。
static声明必须在可见性之后。

<code><span><?php </span><span>namespace</span><span>Vendor</span>\<span>Package</span>;

<span>abstract</span><span><span>class</span><span>ClassName</span>
{</span><span>protected</span><span>static</span><span>$foo</span>;

    <span>abstract</span><span>protected</span><span><span>function</span><span>zim</span><span>()</span>;</span><span>final</span><span>public</span><span>static</span><span><span>function</span><span>bar</span><span>()</span>
    {</span><span>// method body</span>
    }
}</span></code>

方法和函数调用

写方法或函数调用时，方法／函数名 和 左括号( 之间，必须没有空格， 右括号 ) 之前必须没有空格。在参数列表中，逗号间必须没有逗号，每个逗号后必须有一个空格。

<code><span><?php </span><span>$foo</span>->bar(
    <span>$longArgument</span>,
    <span>$longerArgument</span>,
    <span>$muchLongerArgument</span>
);</span></code>

控制结构

控制结构通常遵循以下风格:

1. 控制结构关键词后必须有一个空格。
2. 左括号后必须没有空格。
3. 右括号前必须没有空格。
4. 又括号和左花括号之间必须有一个空格。
5. body必须有一层缩进。
6. 右花括号必须在body下一行。
7. 每个控制结构的body必须用花括号括起来。 即保证外观统一，又减少了添加新行时引入的错误。

if, elseif, else

if 结构如下所示。注意括号、空格、花括号的位置；同时留意 else 和 elseif 与前一部分的 } 在同一行。

<code><span><?php </span><span>if</span> (<span>$expr1</span>) {
    <span>// if body</span>
} <span>elseif</span> (<span>$expr2</span>) {
    <span>// elseif body</span>
} <span>else</span> {
    <span>// else body;</span>
}</span></code>

elseif关键字不应该被 else if 代替。

switch, case

Switch结构如下所示。注意括号、空格和花括号的位置。 case 语句相对于switch必须有一个缩进， break关键字 或者其他终结性的关键字必须和case body在同一缩进层级。在非空的case body，如果没有终结性语句，必须加上注释 // no break。

<code><span><?php </span><span>switch</span> (<span>$expr</span>) {
    <span>case</span><span>0</span>:
        <span>echo</span><span>'First case, with a break'</span>;
        <span>break</span>;
    <span>case</span><span>1</span>:
        <span>echo</span><span>'Second case, which falls through'</span>;
        <span>// no break</span><span>case</span><span>2</span>:
    <span>case</span><span>3</span>:
    <span>case</span><span>4</span>:
        <span>echo</span><span>'Third case, return instead of break'</span>;
        <span>return</span>;
    <span>default</span>:
        <span>echo</span><span>'Default case'</span>;
        <span>break</span>;
}</span></code>

while, do while

while结构如下所示。 注意括号、空格和花括号的位置。

<code><span><?php </span><span>while</span> (<span>$expr</span>) {
    <span>// structure body</span>
}</span></code>

do-while接口如下所示。 注意括号、空格和花括号的位置。

<code><span><?php </span><span>do</span> {
    <span>// structure body;</span>
} <span>while</span> (<span>$expr</span>);</span></code>

for

for 结构如下所示。 注意括号、空格和花括号的位置。

<code><span><?php </span><span>for</span> (<span>$i</span> = <span>0</span>; <span>$i</span> 10</span>; <span>$i</span>++) {
    <span>// for body</span>
}</code>

foreach

foreach 结构如下所示。 注意括号、空格和花括号的位置。

<code><span><?php </span><span>foreach</span> (<span>$iterable</span><span>as</span><span>$key</span> => <span>$value</span>) {
    <span>// foreach body</span>
}</span></code>

try, catch

try-catch区块如下所示。 注意括号、空格和花括号的位置。

<code><span><?php </span><span>try</span> {
    <span>// try body</span>
} <span>catch</span> (FirstExceptionType <span>$e</span>) {
    <span>// catch body</span>
} <span>catch</span> (OtherExceptionType <span>$e</span>) {
    <span>// catch body</span>
}</span></code>

Closure 闭包

声明闭包必须在function关键字后留一个空格，在use关键字前后各留一个空格。

左花括号必须在同一行， 右花括号必须在body的下一行。

参数或变量列表的左括号后 和 右括号前必须没有空格。

参数和变量列表的逗号前必须没有空格，每个逗号后必须有一个空格。

有默认值的参数必须排在最后。

闭包的声明如下所示。 注意括号，逗号，空格和花括号的位置：

<code><span><?php </span><span>$closureWithArgs</span> = <span><span>function</span><span>(<span>$arg1</span>, <span>$arg2</span>)</span> {</span><span>// body</span>
};

<span>$closureWithArgsAndVars</span> = <span><span>function</span><span>(<span>$arg1</span>, <span>$arg2</span>)</span><span>use</span><span>(<span>$var1</span>, <span>$var2</span>)</span> {</span><span>// body</span>
};</span></code>

参数列表和变量列表可以拆分到多行，每个子行有一层缩进。 这么做的时候，第一个列表成员必须独占一行，每行只能有一个列表成员。

参数或变量列表拆分为多行时，到了列表的末尾， 右括号 和 左花括号必须放在同一行，中间有一个空格。

例子：

<code><span><?php </span><span>$longArgs_noVars</span> = <span><span>function</span><span>(
    <span>$longArgument</span>,
    <span>$longerArgument</span>,
    <span>$muchLongerArgument</span>
)</span> {</span><span>// body</span>
};

<span>$noArgs_longVars</span> = <span><span>function</span><span>()</span><span>use</span><span>(
    <span>$longVar1</span>,
    <span>$longerVar2</span>,
    <span>$muchLongerVar3</span>
)</span> {</span><span>// body</span>
};

<span>$longArgs_longVars</span> = <span><span>function</span><span>(
    <span>$longArgument</span>,
    <span>$longerArgument</span>,
    <span>$muchLongerArgument</span>
)</span><span>use</span><span>(
    <span>$longVar1</span>,
    <span>$longerVar2</span>,
    <span>$muchLongerVar3</span>
)</span> {</span><span>// body</span>
};

<span>$longArgs_shortVars</span> = <span><span>function</span><span>(
    <span>$longArgument</span>,
    <span>$longerArgument</span>,
    <span>$muchLongerArgument</span>
)</span><span>use</span><span>(<span>$var1</span>)</span> {</span><span>// body</span>
};

<span>$shortArgs_longVars</span> = <span><span>function</span><span>(<span>$arg</span>)</span><span>use</span><span>(
    <span>$longVar1</span>,
    <span>$longerVar2</span>,
    <span>$muchLongerVar3</span>
)</span> {</span><span>// body</span>
};</span></code>

注意：当闭包被直接作为函数或方法调用的参数时，以上规则同样适用。

<code><span><?php </span><span>$foo</span>->bar(
    <span>$arg1</span>,
    <span><span>function</span><span>(<span>$arg2</span>)</span><span>use</span><span>(<span>$var1</span>)</span> {</span><span>// body</span>
    },
    <span>$arg3</span>
);</span></code>

结语

本指南刻意忽略了许多风格和实践。包括但不限于：

• 声明全局变量和全局常量。
• 声明函数。
• 操作符和赋值。
• 行间对齐。
• 注释和文档区。
• 类名前后缀。
• 最佳实践。

Future recommendations MAY revise and extend this guide to address those or other elements of style and practice.

附录A 调查

In writing this style guide, the group took a survey of member projects to determine common practices. The survey is retained herein for posterity.

调查数据

<code>url,<span>http</span>:<span>//</span>www.horde.org<span>/apps/horde/docs/CODING_STANDARDS,http:/</span><span>/pear.php.net/manual/en/standards.php,http:/</span><span>/solarphp.com/manual/appendix-standards.style,http:/</span><span>/framework.zend.com/manual/en/coding-standard.html,http:/</span><span>/symfony.com/doc/2.0/contributing/code/standards.html,http:/</span><span>/www.ppi.io/docs/coding-standards.html,https:/</span><span>/github.com/ezsystems/ezp-next/wiki/codingstandards,http:/</span><span>/book.cakephp.org/2.0/en/contributing/cakephp-coding-conventions.html,https:/</span><span>/github.com/UnionOfRAD/lithium/wiki/Spec%3A-Coding,http:/</span><span>/drupal.org/coding-standards,http:/</span><span>/code.google.com/p/sabredav/</span>,<span>http</span>:<span>//</span>area51.phpbb.com<span>/docs/31x/coding-guidelines.html,https:/</span><span>/docs.google.com/a/zikula.org/document/edit?authkey=CPCU0Us&hgd=1&id=1fcqb93Sn-hR9c0mkN6m_tyWnmEvoswKBtSc0tKkZmJA,http:/</span><span>/www.chisimba.com,n/a,https:/</span><span>/github.com/Respect/project-info/blob/master/coding-standards-sample.php,n/a,Object Calisthenics for PHP,http:/</span><span>/doc.nette.org/en/coding-standard,http:/</span><span>/flow3.typo3.org,https:/</span><span>/github.com/propelorm/Propel2/wiki/Coding-Standards,http:/</span>/developer.joomla.org/coding-standards.html
voting,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>no</span>,<span>no</span>,<span>no</span>,?,<span>yes</span>,<span>no</span>,<span>yes</span>
indent_type,<span>4</span>,<span>4</span>,<span>4</span>,<span>4</span>,<span>4</span>,tab,<span>4</span>,tab,tab,<span>2</span>,<span>4</span>,tab,<span>4</span>,<span>4</span>,<span>4</span>,<span>4</span>,<span>4</span>,<span>4</span>,tab,tab,<span>4</span>,tab
line_length_limit_soft,<span>75</span>,<span>75</span>,<span>75</span>,<span>75</span>,<span>no</span>,<span>85</span>,<span>120</span>,<span>120</span>,<span>80</span>,<span>80</span>,<span>80</span>,<span>no</span>,<span>100</span>,<span>80</span>,<span>80</span>,?,?,<span>120</span>,<span>80</span>,<span>120</span>,<span>no</span>,<span>150</span>
line_length_limit_hard,<span>85</span>,<span>85</span>,<span>85</span>,<span>85</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>100</span>,?,<span>no</span>,<span>no</span>,<span>no</span>,<span>100</span>,<span>100</span>,?,<span>120</span>,<span>120</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>
class_names,studly,studly,studly,studly,studly,studly,studly,studly,studly,studly,studly,lower_under,studly,lower,studly,studly,studly,studly,?,studly,studly,studly
class_brace_line,next,next,next,next,next,same,next,same,same,same,same,next,next,next,next,next,next,next,next,same,next,next
constant_names,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper,upper
true_false_null,lower,lower,lower,lower,lower,lower,lower,lower,lower,upper,lower,lower,lower,upper,lower,lower,lower,lower,lower,upper,lower,lower
method_names,camel,camel,camel,camel,camel,camel,camel,camel,camel,camel,camel,lower_under,camel,camel,camel,camel,camel,camel,camel,camel,camel,camel
method_brace_line,next,next,next,next,next,same,next,same,same,same,same,next,next,same,next,next,next,next,next,same,next,next
control_brace_line,same,same,same,same,same,same,next,same,same,same,same,next,same,same,next,same,same,same,same,same,same,next
control_space_after,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>no</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>no</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>
always_use_control_braces,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>no</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>no</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>no</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>,<span>yes</span>
else_elseif_line,same,same,same,same,same,same,next,same,same,next,same,next,same,next,next,same,same,same,same,same,same,next
case_break_indent_from_switch,<span>0</span>/<span>1</span>,<span>0</span>/<span>1</span>,<span>0</span>/<span>1</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>1</span>,<span>1</span>/<span>1</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>1</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>,<span>0</span>/<span>1</span>,<span>1</span>/<span>1</span>,<span>1</span>/<span>2</span>,<span>1</span>/<span>2</span>
function_space_after,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>
closing_php_tag_required,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>yes</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>yes</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>yes</span>,<span>no</span>,<span>no</span>
line_endings,LF,LF,LF,LF,LF,LF,LF,LF,?,LF,?,LF,LF,LF,LF,?,,LF,?,LF,LF,LF
static_or_visibility_first,static,?,static,either,either,either,visibility,visibility,visibility,either,static,either,?,visibility,?,?,either,either,visibility,visibility,static,?
control_space_parens,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>yes</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>yes</span>,?,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>
blank_line_after_php,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>yes</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>no</span>,<span>yes</span>,<span>yes</span>,<span>no</span>,<span>no</span>,<span>yes</span>,?,<span>yes</span>,<span>yes</span>,<span>no</span>,<span>yes</span>,<span>no</span>,<span>yes</span>,<span>no</span>
class_method_control_brace,next/next/same,next/next/same,next/next/same,next/next/same,next/next/same,same/same/same,next/next/next,same/same/same,same/same/same,same/same/same,same/same/same,next/next/next,next/next/same,next/same/same,next/next/next,next/next/same,next/next/same,next/next/same,next/next/same,same/same/same,next/next/same,next/next/next</code>

调查说明

indent_type: The type of indenting. tab = “Use a tab”, 2 or 4 = “number of spaces”

line_length_limit_soft: The “soft” line length limit, in characters. ? = not discernible or no response, no means no limit.

line_length_limit_hard: The “hard” line length limit, in characters. ? = not discernible or no response, no means no limit.

class_names: How classes are named. lower = lowercase only, lower_under = lowercase with underscore separators, studly = StudlyCase.

class_brace_line: Does the opening brace for a class go on the same line as the class keyword, or on the next line after it?

constant_names: How are class constants named? upper = Uppercase with underscore separators.

true_false_null: Are the true, false, and null keywords spelled as all lower case, or all upper case?

method_names: How are methods named? camel = camelCase, lower_under = lowercase with underscore separators.

method_brace_line: Does the opening brace for a method go on the same line as the method name, or on the next line?

control_brace_line: Does the opening brace for a control structure go on the same line, or on the next line?

control_space_after: Is there a space after the control structure keyword?

always_use_control_braces: Do control structures always use braces?

else_elseif_line: When using else or elseif, does it go on the same line as the previous closing brace, or does it go on the next line?

case_break_indent_from_switch: How many times are case and break indented from an opening switch statement?

function_space_after: Do function calls have a space after the function name and before the opening parenthesis?

closing_php_tag_required: In files containing only PHP, is the closing ?> tag required?

line_endings: What type of line ending is used?

static_or_visibility_first: When declaring a method, does static come first, or does the visibility come first?

control_space_parens: In a control structure expression, is there a space after the opening parenthesis and a space before the closing parenthesis? yes = if ( expr),no=if($expr ), no = if ($expr).

blank_line_after_php: Is there a blank line after the opening PHP tag?

class_method_control_brace: A summary of what line the opening braces go on for classes, methods, and control structures.

调查结果

<code><span>indent_type:</span>
    tab: <span>7</span><span>2</span>: <span>1</span><span>4</span>: <span>14</span><span>line_length_limit_soft:</span>
    ?: <span>2</span>
    no: <span>3</span><span>75</span>: <span>4</span><span>80</span>: <span>6</span><span>85</span>: <span>1</span><span>100</span>: <span>1</span><span>120</span>: <span>4</span><span>150</span>: <span>1</span><span>line_length_limit_hard:</span>
    ?: <span>2</span>
    no: <span>11</span><span>85</span>: <span>4</span><span>100</span>: <span>3</span><span>120</span>: <span>2</span><span>class_names:</span>
    ?: <span>1</span>
    lower: <span>1</span>
    lower_under: <span>1</span>
    studly: <span>19</span><span>class_brace_line:</span>
    next: <span>16</span>
    same: <span>6</span><span>constant_names:</span>
    upper: <span>22</span><span>true_false_null:</span>
    lower: <span>19</span>
    upper: <span>3</span><span>method_names:</span>
    camel: <span>21</span>
    lower_under: <span>1</span><span>method_brace_line:</span>
    next: <span>15</span>
    same: <span>7</span><span>control_brace_line:</span>
    next: <span>4</span>
    same: <span>18</span><span>control_space_after:</span>
    no: <span>2</span>
    yes: <span>20</span><span>always_use_control_braces:</span>
    no: <span>3</span>
    yes: <span>19</span><span>else_elseif_line:</span>
    next: <span>6</span>
    same: <span>16</span><span>case_break_indent_from_switch:</span><span>0</span>/<span>1</span>: <span>4</span><span>1</span>/<span>1</span>: <span>4</span><span>1</span>/<span>2</span>: <span>14</span><span>function_space_after:</span>
    no: <span>22</span><span>closing_php_tag_required:</span>
    no: <span>19</span>
    yes: <span>3</span><span>line_endings:</span>
    ?: <span>5</span>
    LF: <span>17</span><span>static_or_visibility_first:</span>
    ?: <span>5</span>
    either: <span>7</span>
    static: <span>4</span>
    visibility: <span>6</span><span>control_space_parens:</span>
    ?: <span>1</span>
    no: <span>19</span>
    yes: <span>2</span><span>blank_line_after_php:</span>
    ?: <span>1</span>
    no: <span>13</span>
    yes: <span>8</span><span>class_method_control_brace:</span>
    next/next/next: <span>4</span>
    next/next/same: <span>11</span>
    next/same/same: <span>1</span>
    same/same/same: <span>6</span></code>

以上就介绍了PHP编码风格指南 (PHP-FIG PSR-2)，包括了方面的内容，希望对PHP教程有兴趣的朋友有所帮助。