gettype

實例

返回不同變量的類型：

 <span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$a</span> <span class="token operator">=</span> <span class="token number">3</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">gettype</span> <span class="token punctuation">(</span> <span class="token variable">$a</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$b</span> <span class="token operator">=</span> <span class="token number">3.2</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">gettype</span> <span class="token punctuation">(</span> <span class="token variable">$b</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$c</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"Hello"</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">gettype</span> <span class="token punctuation">(</span> <span class="token variable">$c</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$d</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">gettype</span> <span class="token punctuation">(</span> <span class="token variable">$d</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$e</span> <span class="token operator">=</span> <span class="token keyword">array</span> <span class="token punctuation">(</span> <span class="token string double-quoted-string">"red"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"green"</span> <span class="token punctuation">,</span> <span class="token string double-quoted-string">"blue"</span> <span class="token punctuation">)</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">gettype</span> <span class="token punctuation">(</span> <span class="token variable">$e</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$f</span> <span class="token operator">=</span> <span class="token constant">NULL</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">gettype</span> <span class="token punctuation">(</span> <span class="token variable">$f</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>

<span class="token variable">$g</span> <span class="token operator">=</span> <span class="token constant boolean">false</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token function">gettype</span> <span class="token punctuation">(</span> <span class="token variable">$g</span> <span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"<br>"</span> <span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

親自試一試

例子解釋：

gettype()函數用於檢查不同類型的變量（整數、浮點數、字符串、數組、空值和布爾值）並返回它們的類型。例如，對於整數變量$a ， gettype($a)將返回字符串"integer" 。對於浮點數變量$b ，它將返回"double" ，對於字符串變量$c ，它將返回"string" ，依此類推。如果變量是關閉的資源，在PHP 7.2 及更高版本中， gettype()將返回"resource (closed)" ，而在早期版本中，它可能返回"unknown type" 。