# 自动加载spl\_autoload\_register 注册给定的函数作为 \_\_autoload 的实现 ``` <pre class="calibre17">``` <span class="token5">function</span> <span class="token4">my_autoloader</span><span class="token3">(</span>$class<span class="token3">)</span> <span class="token3">{</span> include <span class="token2">'classes/'</span> <span class="token3">.</span> $class <span class="token4"><span class="token3">.</span></span> <span class="token2">'.class.php'</span><span class="token3">;</span> <span class="token3">}</span> <span class="token4">spl_autoload_register</span><span class="token3">(</span><span class="token2">'my_autoloader'</span><span class="token3">)</span><span class="token3">;</span> 例子讲解： <span class="token5">function</span> <span class="token4">_autoload</span><span class="token3">(</span>$class<span class="token3">)</span><span class="token3">{</span> include $class <span class="token4"><span class="token3">.</span></span> <span class="token2">'.php'</span><span class="token3">;</span> <span class="token3">}</span> <span class="token4">spl_autoload_register</span><span class="token3">(</span><span class="token2">'_autoload'</span><span class="token3">)</span><span class="token3">;</span> $dog <span class="token1">=</span> <span class="token5">new</span> <span class="token4">dog</span><span class="token3">(</span><span class="token3">)</span><span class="token3">;</span> 当实例化不存在的类时，spl_autoload_register会更具他的参数找到参数对应的函数或者类的静态方法，并将这个不存在的类名当作参数传入函数了类方法中 <span class="token">// 或者，自 PHP 5.3.0 起可以使用一个匿名函数</span> <span class="token4">spl_autoload_register</span><span class="token3">(</span><span class="token5">function</span> <span class="token3">(</span>$class<span class="token3">)</span> <span class="token3">{</span> include <span class="token2">'classes/'</span> <span class="token3">.</span> $class <span class="token4"><span class="token3">.</span></span> <span class="token2">'.class.php'</span><span class="token3">;</span> <span class="token3">}</span><span class="token3">)</span><span class="token3">;</span> ``` ```