is_file
判断给定文件名是否为一个正常的文件
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token variable">$file</span> <span class="token operator">=</span> <span class="token string double-quoted-string">"test.txt"</span><span class="token punctuation">;</span> <span class="token keyword">if</span><span class="token punctuation">(</span><span class="token function">is_file</span><span class="token punctuation">(</span><span class="token variable">$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 punctuation">(</span><span class="token string double-quoted-string">"<span class="token interpolation"><span class="token variable">$file</span></span> is a regular file"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token keyword">else</span> <span class="token punctuation">{</span> <span class="token keyword">echo</span> <span class="token punctuation">(</span><span class="token string double-quoted-string">"<span class="token interpolation"><span class="token variable">$file</span></span> is not a regular file"</span><span class="token punctuation">)</span><span class="token punctuation">;</span> <span class="token punctuation">}</span> <span class="token delimiter important">?></span></span>
输出:
test.txt is a regular file
<span class="token php language-php"><span class="token delimiter important"><?php</span> <span class="token function">var_dump</span><span class="token punctuation">(</span><span class="token function">is_file</span><span class="token punctuation">(</span><span class="token string single-quoted-string">'a_file.txt'</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"\n"</span><span class="token punctuation">;</span> <span class="token function">var_dump</span><span class="token punctuation">(</span><span class="token function">is_file</span><span class="token punctuation">(</span><span class="token string single-quoted-string">'/usr/bin/'</span><span class="token punctuation">)</span><span class="token punctuation">)</span> <span class="token operator">.</span> <span class="token string double-quoted-string">"\n"</span><span class="token punctuation">;</span> <span class="token delimiter important">?></span></span>
输出:
bool(true) bool(false)