is_countable

例

変数のコンテンツが数える値であるかどうかを確認します。

 <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 string double-quoted-string">"hello"</span> <span class="token punctuation">;</span>
<span class="token keyword">エコー</span><span class="token string double-quoted-string">「a is」</span> <span class="token operator">。</span> <span class="token function">is_countable</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 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">エコー</span><span class="token string double-quoted-string">「b is」</span> <span class="token operator">。</span> <span class="token function">is_countable</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 keyword">array</span> <span class="token punctuation">（</span> <span class="token string double-quoted-string">"peter"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"35"</span> <span class="token punctuation">、</span> <span class="token string double-quoted-string">"ben"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"37"</span> <span class="token punctuation">、</span> <span class="token string double-quoted-string">"joe"</span> <span class="token operator">=></span> <span class="token string double-quoted-string">"43"</span> <span class="token punctuation">）</span> <span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"c is"</span> <span class="token operator">。</span> <span class="token function">is_countable</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 punctuation">$</span> <span class="token variable">d</span> <span class="token operator">=</span> <span class="token punctuation">[</span> <span class="token number">1、2、3</span> <span class="token number">]</span> <span class="token punctuation">;</span><span class="token number">​</span><span class="token punctuation">​</span><span class="token punctuation">​</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"d is"</span> <span class="token operator">。</span> <span class="token function">is_countable</span> <span class="token punctuation">（</span> <span class="token variable">$ 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 delimiter important">？></span></span>

自分で試してみてください

例説明：

変数$aには文字列が含まれていますが、これは可算値ではないため、 is_countable($a)がFALSEを返します。変数$b 、 $cおよび$dには、カスタイル値であるアレイが含まれているため、 is_countable($b) 、 is_countable($c) 、 is_countable($d)はすべてTRUEを返します。インデックス配列であろうと連想配列であろうと、配列はカウント可能です。