PHP输出当前进程所有变量/常量/模块/函数/类的示例
PHP输出当前进程所有变量、常量、模块、函数、类的示例
1. get_defined_vars (PHP 4 >= 4.0.4, PHP 5) — 获取由所有已定义变量所组成的数组
array get_defined_vars ( void )
此函数返回一个包含所有已定义变量列表的多维数组,这些变量包括环境变量、服务器变量和用户定义的变量。
复制代码 代码如下:
echo '
';<br>$b = array(1,1,2,3,5,8);<br>$arr = get_defined_vars();<br>// 打印 $b<br>print_r($arr["b"]);<br>// 打印所有服务器变量<br>print_r($arr["_SERVER"]);<br>// 打印变量数组的所有可用键值<br>print_r(array_keys(get_defined_vars()));<br>?><br>2. get_defined_functions (PHP 4 >= 4.0.4, PHP 5) — 获取所有已经定义的函数<br>array get_defined_functions ( void ) //void 表示为空,,不需要任何参数<br><?php <BR>echo '<pre class="brush:php;toolbar:false">';<br>function foo()<br>{<br> echo "This is my function foo";<br>}<br>$arr = get_defined_functions();<br>print_r($arr);<br>?><br><br>3. get_loaded_extensions (PHP 4, PHP 5) — 获取所有可用的模块<br><p><span>复制代码</span> 代码如下:</p><p><br><?php <BR>echo '</p><pre class="brush:php;toolbar:false">';<br>print_r(get_loaded_extensions());<br>?><br><br>4. get_extension_funcs (PHP 4, PHP 5) — 获取指定模块的可用函数<br>array get_extension_funcs ( string $module_name ) 该函数返回指定模块所有可用的函数。传入的参数(模块名称)必须是小写<br><p><span>复制代码</span> 代码如下:</p><p><br><?php <BR>echo '</p><pre class="brush:php;toolbar:false">';<br>print_r(get_extension_funcs("gd"));<br>print_r(get_extension_funcs("xml"));<br>?><br><br>5. get_defined_constants (PHP 4 >= 4.1.0, PHP 5) — 获取关联数组的名字所有的常量和他们的价值<br>array get_defined_constants ([ bool $categorize = false ] )<br><p><span>复制代码</span> 代码如下:</p><p><br><?php <BR>echo '</p><pre class="brush:php;toolbar:false">';<br>define("MY_CONSTANT", 1);<br>print_r(get_defined_constants(true));<br>?><br><br>6. get_declared_classes (PHP 4, PHP 5) — 获取由已定义类的名字所组成的数组<br> array get_declared_classes ( void )<br><p><span>复制代码</span> 代码如下:</p><p><br><?php <BR>echo '</p><pre class="brush:php;toolbar:false">';<br>//define classone<br>class classone { }<br>//define classtwo<br>class classtwo { }<br>//This will show X classes (built-ins, extensions etc) with<br>//classone and classtwo as the last two elements<br>print_r(get_declared_classes());<br>//define classthree<br>class classthree { }<br>//...and four<br>class classfour { }<br>//Shows the same result as before with class three and four appended<br>print_r(get_declared_classes());<br>?><br>

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