如何使用mb_str_split函数来拆分多字节字符串，步骤和示例详解

gitbox 2025-09-19
<span><span><span class="hljs-meta">&lt;?php</span></span><span>
</span><span><span class="hljs-comment">// 这里是与文章内容无关的PHP代码示例</span></span><span>
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"欢迎使用PHP多字节字符串拆分教程！"</span></span><span>;
</span><span><span class="hljs-meta">?&gt;</span></span><span>

&lt;hr&gt;

</span><span><span class="hljs-meta">&lt;?php</span></span><span>
<span class="hljs-comment">/*
文章标题：如何使用mb_str_split函数来拆分多字节字符串，步骤和示例详解
*/</span>

</span><span><span class="hljs-comment">// 在PHP中处理多字节字符串时，普通的字符串函数可能无法正确识别中文、日文、韩文等字符。</span></span><span>
</span><span><span class="hljs-comment">// 从PHP 7.4开始，提供了mb_str_split函数，专门用于将多字节字符串拆分成单个字符或指定长度的子串。</span></span><span>

</span><span><span class="hljs-comment">// 1. 基本用法</span></span><span>
</span><span><span class="hljs-variable">$string</span></span><span> = </span><span><span class="hljs-string">"你好，世界！"</span></span><span>;
</span><span><span class="hljs-variable">$chars</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mb_str_split</span></span><span>(</span><span><span class="hljs-variable">$string</span></span><span>);
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"基本拆分结果：\n"</span></span><span>;
</span><span><span class="hljs-title function_ invoke__">print_r</span></span><span>(</span><span><span class="hljs-variable">$chars</span></span><span>);

</span><span><span class="hljs-comment">// 输出结果:</span></span><span>
</span><span><span class="hljs-comment">// Array</span></span><span>
</span><span><span class="hljs-comment">// (</span></span><span>
</span><span><span class="hljs-comment">//     [0] =&gt; 你</span></span><span>
</span><span><span class="hljs-comment">//     [1] =&gt; 好</span></span><span>
</span><span><span class="hljs-comment">//     [2] =&gt; ，</span></span><span>
</span><span><span class="hljs-comment">//     [3] =&gt; 世</span></span><span>
</span><span><span class="hljs-comment">//     [4] =&gt; 界</span></span><span>
</span><span><span class="hljs-comment">//     [5] =&gt; ！</span></span><span>
</span><span><span class="hljs-comment">// )</span></span><span>

</span><span><span class="hljs-comment">// 2. 指定长度拆分</span></span><span>
</span><span><span class="hljs-comment">// 可以通过第二个参数指定每段子串的长度</span></span><span>
</span><span><span class="hljs-variable">$parts</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mb_str_split</span></span><span>(</span><span><span class="hljs-variable">$string</span></span><span>, </span><span><span class="hljs-number">2</span></span><span>);
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"每两字符拆分结果：\n"</span></span><span>;
</span><span><span class="hljs-title function_ invoke__">print_r</span></span><span>(</span><span><span class="hljs-variable">$parts</span></span><span>);

</span><span><span class="hljs-comment">// 输出结果:</span></span><span>
</span><span><span class="hljs-comment">// Array</span></span><span>
</span><span><span class="hljs-comment">// (</span></span><span>
</span><span><span class="hljs-comment">//     [0] =&gt; 你好</span></span><span>
</span><span><span class="hljs-comment">//     [1] =&gt; ，世</span></span><span>
</span><span><span class="hljs-comment">//     [2] =&gt; 界！</span></span><span>
</span><span><span class="hljs-comment">// )</span></span><span>

</span><span><span class="hljs-comment">// 3. 设置字符编码</span></span><span>
</span><span><span class="hljs-comment">// mb_str_split默认使用内部字符编码（通常是UTF-8），也可以指定编码</span></span><span>
</span><span><span class="hljs-variable">$charsUtf8</span></span><span> = </span><span><span class="hljs-title function_ invoke__">mb_str_split</span></span><span>(</span><span><span class="hljs-variable">$string</span></span><span>, </span><span><span class="hljs-number">1</span></span><span>, </span><span><span class="hljs-string">"UTF-8"</span></span><span>);
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"UTF-8编码拆分结果：\n"</span></span><span>;
</span><span><span class="hljs-title function_ invoke__">print_r</span></span><span>(</span><span><span class="hljs-variable">$charsUtf8</span></span><span>);

</span><span><span class="hljs-comment">// 4. 应用场景示例</span></span><span>
</span><span><span class="hljs-comment">// - 对用户输入的多字节字符串进行逐字符处理，如表情过滤或敏感词检查</span></span><span>
</span><span><span class="hljs-comment">// - 将字符串拆分后逐个显示在界面上</span></span><span>
</span><span><span class="hljs-comment">// - 统计多字节字符串长度并进行切分</span></span><span>

</span><span><span class="hljs-comment">// 示例：统计字符串长度</span></span><span>
</span><span><span class="hljs-variable">$length</span></span><span> = </span><span><span class="hljs-title function_ invoke__">count</span></span><span>(</span><span><span class="hljs-title function_ invoke__">mb_str_split</span></span><span>(</span><span><span class="hljs-variable">$string</span></span><span>));
</span><span><span class="hljs-keyword">echo</span></span><span> </span><span><span class="hljs-string">"字符串长度为: "</span></span><span> . </span><span><span class="hljs-variable">$length</span></span><span> . </span><span><span class="hljs-string">" 个字符\n"</span></span><span>;

</span><span><span class="hljs-comment">// 总结：</span></span><span>
</span><span><span class="hljs-comment">// mb_str_split是处理多字节字符串的高效工具，能够避免使用传统函数可能出现的乱码问题。</span></span><span>
</span><span><span class="hljs-comment">// 只需传入字符串，按需设置每段长度和编码，即可轻松完成拆分任务。</span></span><span>
</span><span><span class="hljs-meta">?&gt;</span></span><span>
</span></span>
mb_str_split