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    2 => '找出最小值',
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?>
<div id="function.min" class="refentry">
 <div class="refnamediv">
  <h1 class="refname">min</h1>
  <p class="verinfo">(PHP 4, PHP 5, PHP 7, PHP 8)</p><p class="refpurpose"><span class="refname">min</span> &mdash; <span class="dc-title">找出最小值</span></p>

 </div>
 <div class="refsect1 description" id="refsect1-function.min-description">
  <h3 class="title">说明</h3>
   <div class="methodsynopsis dc-description">
    <span class="methodname"><strong>min</strong></span>(<span class="methodparam"><span class="type"><a href="language.types.mixed.php" class="type mixed">mixed</a></span> <code class="parameter">$value</code></span>, <span class="methodparam"><span class="type"><a href="language.types.mixed.php" class="type mixed">mixed</a></span> <code class="parameter">...$values</code></span>): <span class="type"><a href="language.types.mixed.php" class="type mixed">mixed</a></span></div>

   <p class="simpara">替代签名（不支持命名参数）：</p>
   <div class="methodsynopsis dc-description"><span class="methodname"><strong>min</strong></span>(<span class="methodparam"><span class="type"><a href="language.types.array.php" class="type array">array</a></span> <code class="parameter">$value_array</code></span>): <span class="type"><a href="language.types.mixed.php" class="type mixed">mixed</a></span></div>

  <p class="para rdfs-comment">
   如果仅有一个参数且为数组，<span class="function"><strong>min()</strong></span>
   返回该数组中最小的值。如果给出了两个或更多参数,
   <span class="function"><strong>min()</strong></span> 会返回这些值中最小的一个。
  </p>
  <blockquote class="note"><p><strong class="note">注意</strong>: 
   <p class="para">
    不同类型的值将使用<a href="language.operators.comparison.php" class="link">标准比较规则</a>进行比较。例如，一个非数字
    <span class="type"><a href="language.types.string.php" class="type string">string</a></span> 与 <span class="type"><a href="language.types.integer.php" class="type int">int</a></span> 比较时就当做是 <code class="literal">0</code>，但多个非数字
    <span class="type"><a href="language.types.string.php" class="type string">string</a></span> 值将会按照字母数字比较。返回的实际值是未应用任何转换的原始类型。
   </p>
  </p></blockquote>
  <div class="caution"><strong class="caution">警告</strong>
   <p class="simpara">
    传递不同类型的参数时要小心，因为 <span class="function"><strong>min()</strong></span> 会产生不可预测的结果。
   </p>
  </div>
 </div>

  <div class="refsect1 parameters" id="refsect1-function.min-parameters">
  <h3 class="title">参数</h3>
  <p class="para">
   <dl>
    
     <dt><code class="parameter">value</code></dt>
     <dd>
      <p class="para">
       任何<a href="language.operators.comparison.php" class="link">可比较</a>的值。
      </p>
     </dd>
    
    
     <dt><code class="parameter">values</code></dt>
     <dd>
      <p class="para">
       任何<a href="language.operators.comparison.php" class="link">可比较</a>的值。
      </p>
     </dd>
    
    
     <dt><code class="parameter">value_array</code></dt>
     <dd>
      <p class="para">
       包含值的数组。
      </p>
     </dd>
    
   </dl>
  </p>
 </div>

 <div class="refsect1 returnvalues" id="refsect1-function.min-returnvalues">
  <h3 class="title">返回值</h3>
  <p class="para">
   <span class="function"><strong>min()</strong></span> 根据标准比较返回认为是“最小”的参数值。如果不同类型的多个值认为相等（比如
   <code class="literal">0</code> 与 <code class="literal">&#039;abc&#039;</code>），则将会返回提供给函数的第一个值。
  </p>
 </div>


 <div class="refsect1 errors" id="refsect1-function.min-errors">
  <h3 class="title">错误／异常</h3>
  <p class="para">
   如果传递空数组，<span class="function"><strong>min()</strong></span> 抛出 <span class="classname"><a href="class.valueerror.php" class="classname">ValueError</a></span>。
  </p>
 </div>


 <div class="refsect1 changelog" id="refsect1-function.min-changelog">
  <h3 class="title">更新日志</h3>
  <table class="doctable informaltable">
   
    <thead>
     <tr>
      <th>版本</th>
      <th>说明</th>
     </tr>

    </thead>

    <tbody class="tbody">
     <tr>
      <td>8.0.0</td>
      <td>
       <span class="function"><strong>min()</strong></span> 现在失败时会抛出 <span class="classname"><a href="class.valueerror.php" class="classname">ValueError</a></span>；之前会返回 
       <strong><code><a href="reserved.constants.php#constant.false">false</a></code></strong> 并发出 <strong><code><a href="errorfunc.constants.php#constant.e-warning">E_WARNING</a></code></strong> 错误。
      </td>
     </tr>

     <tr>
      <td>8.0.0</td>
      <td>
       由于 <a href="migration80.incompatible.php#migration80.incompatible.core.string-number-comparision" class="link">字符串到数字的比较</a>
       已经改变，<span class="function"><strong>min()</strong></span> 在这些情况下不再根据参数的顺序返回不同的值。
      </td>
     </tr>

    </tbody>
   
  </table>

 </div>


 <div class="refsect1 examples" id="refsect1-function.min-examples">
  <h3 class="title">示例</h3>
  <p class="para">
   <div class="example" id="example-1">
    <p><strong>示例 #1 <span class="function"><strong>min()</strong></span> 用法的示例</strong></p>
    <div class="example-contents">
<div class="annotation-interactive phpcode"><code><span style="color: #000000"><span style="color: #0000BB">&lt;?php<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">min</span><span style="color: #007700">(</span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">3</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #0000BB">6</span><span style="color: #007700">, </span><span style="color: #0000BB">7</span><span style="color: #007700">), </span><span style="color: #0000BB">PHP_EOL</span><span style="color: #007700">;  </span><span style="color: #FF8000">// 1<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">min</span><span style="color: #007700">(array(</span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">4</span><span style="color: #007700">, </span><span style="color: #0000BB">5</span><span style="color: #007700">)), </span><span style="color: #0000BB">PHP_EOL</span><span style="color: #007700">; </span><span style="color: #FF8000">// 2<br /><br />// Here we are comparing -1 &lt; 0, so -1 is the lowest value<br /></span><span style="color: #007700">echo </span><span style="color: #0000BB">min</span><span style="color: #007700">(</span><span style="color: #DD0000">'hello'</span><span style="color: #007700">, -</span><span style="color: #0000BB">1</span><span style="color: #007700">), </span><span style="color: #0000BB">PHP_EOL</span><span style="color: #007700">;    </span><span style="color: #FF8000">// -1<br /><br />// With multiple arrays of different lengths, min returns the shortest<br /></span><span style="color: #0000BB">$val </span><span style="color: #007700">= </span><span style="color: #0000BB">min</span><span style="color: #007700">(array(</span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">2</span><span style="color: #007700">), array(</span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">)); </span><span style="color: #FF8000">// array(2, 2, 2)<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$val</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// Multiple arrays of the same length are compared from left to right<br />// so in our example: 2 == 2, but 4 &lt; 5<br /></span><span style="color: #0000BB">$val </span><span style="color: #007700">= </span><span style="color: #0000BB">min</span><span style="color: #007700">(array(</span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">4</span><span style="color: #007700">, </span><span style="color: #0000BB">8</span><span style="color: #007700">), array(</span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">5</span><span style="color: #007700">, </span><span style="color: #0000BB">1</span><span style="color: #007700">)); </span><span style="color: #FF8000">// array(2, 4, 8)<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$val</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// 如果同时给出数组和非数组，则绝对不会返回数组<br />// 因为比较认为数组大于任何值<br /></span><span style="color: #0000BB">$val </span><span style="color: #007700">= </span><span style="color: #0000BB">min</span><span style="color: #007700">(</span><span style="color: #DD0000">'string'</span><span style="color: #007700">, array(</span><span style="color: #0000BB">2</span><span style="color: #007700">, </span><span style="color: #0000BB">5</span><span style="color: #007700">, </span><span style="color: #0000BB">7</span><span style="color: #007700">), </span><span style="color: #0000BB">42</span><span style="color: #007700">);   </span><span style="color: #FF8000">// string<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$val</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// If one argument is NULL or a boolean, it will be compared against<br />// other values using the rules FALSE &lt; TRUE and NULL == FALSE regardless of the <br />// other types involved<br />// In the below examples, both -10 and 10 are treated as TRUE in the comparison<br /></span><span style="color: #0000BB">$val </span><span style="color: #007700">= </span><span style="color: #0000BB">min</span><span style="color: #007700">(-</span><span style="color: #0000BB">10</span><span style="color: #007700">, </span><span style="color: #0000BB">FALSE</span><span style="color: #007700">, </span><span style="color: #0000BB">10</span><span style="color: #007700">); </span><span style="color: #FF8000">// FALSE<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$val</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">$val </span><span style="color: #007700">= </span><span style="color: #0000BB">min</span><span style="color: #007700">(-</span><span style="color: #0000BB">10</span><span style="color: #007700">, </span><span style="color: #0000BB">NULL</span><span style="color: #007700">, </span><span style="color: #0000BB">10</span><span style="color: #007700">);  </span><span style="color: #FF8000">// NULL<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$val</span><span style="color: #007700">);<br /><br /></span><span style="color: #FF8000">// 0, on the other hand, is treated as FALSE, so is "lower than" TRUE<br /></span><span style="color: #0000BB">$val </span><span style="color: #007700">= </span><span style="color: #0000BB">min</span><span style="color: #007700">(</span><span style="color: #0000BB">0</span><span style="color: #007700">, </span><span style="color: #0000BB">TRUE</span><span style="color: #007700">); </span><span style="color: #FF8000">// 0<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$val</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span></span></code></div>
    </div>

   </div>
  </p>
 </div>

 
 <div class="refsect1 seealso" id="refsect1-function.min-seealso">
  <h3 class="title">参见</h3>
  <p class="para">
   <ul class="simplelist">
    <li><span class="function"><a href="function.max.php" class="function" rel="rdfs-seeAlso">max()</a> - 找出最大值</span></li>
    <li><span class="function"><a href="function.count.php" class="function" rel="rdfs-seeAlso">count()</a> - 统计数组、Countable 对象中所有元素的数量</span></li>
   </ul>
  </p>
 </div>

</div><?php manual_footer($setup); ?>