is_resource

名称:is_resource

分类:变量处理

所属语言:php

一句话介绍:检查变量是否为资源类型。

实例

检查变量是否是资源：

<span class="token php language-php"><span class="token delimiter important"><?php</span>
<span class="token variable">$file</span> <span class="token operator">=</span> <span class="token function">fopen</span><span class="token punctuation">(</span><span class="token string double-quoted-string">"test.txt"</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"r"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token keyword">if</span> <span class="token punctuation">(</span><span class="token function">is_resource</span><span class="token punctuation">(</span><span class="token variable">$file</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">"File is open"</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token punctuation">{</span>
  <span class="token keyword">echo</span> <span class="token string double-quoted-string">"Error open file"</span><span class="token punctuation">;</span>
<span class="token punctuation">}</span>
<span class="token delimiter important">?></span></span>

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