is_callable

名称:is_callable

分类:变量处理

所属语言:php

一句话介绍:检查变量的内容是否可作为函数调用。

实例

检查变量的内容是否可以作为函数调用：

<span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token keyword">function</span> <span class="token function-definition function">test1</span><span class="token punctuation">(</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 string double-quoted-string">"test1 is callable: "</span> <span class="token operator">.</span> <span class="token function">is_callable</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"test1"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"<br>"</span><span class="token punctuation">;</span>
<span class="token keyword">echo</span> <span class="token string double-quoted-string">"test2 is callable: "</span> <span class="token operator">.</span> <span class="token function">is_callable</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"test2"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>
<span class="token delimiter important">?></span></span>

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