get_defined_vars

實例

以數組形式返回所有定義的變量：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>

<span class="token variable">$arr</span> <span class="token operator">=</span> <span class="token function">get_defined_vars</span> <span class="token punctuation">(</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>

<span class="token function">print_r</span> <span class="token punctuation">(</span> <span class="token variable">$arr</span> <span class="token punctuation">[</span> <span class="token string double-quoted-string">"a"</span> <span class="token punctuation">]</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

親自試一試

例子解釋：

在這個例子中， $a是一個包含三個顏色字符串的數組。調用get_defined_vars()後，它返回一個數組$arr ，該數組包含當前作用域中定義的所有變量。然後通過print_r($arr["a"])輸出$a變量的內容，即顏色數組。請注意， get_defined_vars()返回的數組鍵是變量名，對應的值是變量的值。