ftell

实例

<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 comment">// 输出当前位置</span>
<span class="token keyword">echo</span> <span class="token function">ftell</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 comment">// 改变当前位置</span>
<span class="token function">fseek</span><span class="token punctuation">(</span><span class="token variable">$file</span><span class="token punctuation">,</span><span class="token string double-quoted-string">"15"</span><span class="token punctuation">)</span><span class="token punctuation">;</span>

<span class="token comment">// 再次输出当前位置</span>
<span class="token keyword">echo</span> <span class="token function">ftell</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 function">fclose</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 delimiter important">?></span></span>

输出：

0
15