function.array-multisort.html

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<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$ar&nbsp;</span><span style="color: #007700">=&nbsp;array(<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;array(</span><span style="color: #DD0000">"10"</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">11</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">100</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">100</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"a"</span><span style="color: #007700">),<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;array(&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">,&nbsp;&nbsp;</span><span style="color: #0000BB">2</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">"2"</span><span style="color: #007700">,&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">3</span><span style="color: #007700">,&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">)<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;);<br /></span><span style="color: #0000BB">array_multisort</span><span style="color: #007700">(</span><span style="color: #0000BB">$ar</span><span style="color: #007700">[</span><span style="color: #0000BB">0</span><span style="color: #007700">],&nbsp;</span><span style="color: #0000BB">SORT_ASC</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">SORT_STRING</span><span style="color: #007700">,<br />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">$ar</span><span style="color: #007700">[</span><span style="color: #0000BB">1</span><span style="color: #007700">],&nbsp;</span><span style="color: #0000BB">SORT_NUMERIC</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">SORT_DESC</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">var_dump</span><span style="color: #007700">(</span><span style="color: #0000BB">$ar</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>
     In this example, after sorting, the first array will transform to
     &quot;10&quot;, 100, 100, 11, &quot;a&quot; (it was sorted as strings in ascending
     order). The second will contain 1, 3, &quot;2&quot;, 2, 1 (sorted as numbers,
     in descending order).
    </p></div>
    <div class="example-contents"><pre>
<div class="cdata"><pre>
array(2) {
  [0]=&gt; array(5) {
    [0]=&gt; string(2) &quot;10&quot;
    [1]=&gt; int(100)
    [2]=&gt; int(100)
    [3]=&gt; int(11)
    [4]=&gt; string(1) &quot;a&quot;
  }
  [1]=&gt; array(5) {
    [0]=&gt; int(1)
    [1]=&gt; int(3)
    [2]=&gt; string(1) &quot;2&quot;
    [3]=&gt; int(2)
    [4]=&gt; int(1)
  }
}
</pre></div>
    </pre></div>
   </div>
  </p>
  <p class="para">
   <div class="example">
    <p><b>Example #3 Sorting database results</b></p>
    <div class="example-contents"><p>
     For this example, each element in the <var class="varname">data</var>
     array represents one row in a table. This type of dataset is typical
     of database records.
    </p></div>
    <div class="example-contents"><p>
     Example data:
    </p></div>
    <div class="example-contents"><pre>
<div class="cdata"><pre>
volume | edition
-------+--------
    67 |       2
    86 |       1
    85 |       6
    98 |       2
    86 |       6
    67 |       7
</pre></div>
    </pre></div>
    <div class="example-contents"><p>
     The data as an array, called <var class="varname">data</var>. This would usually,
     for example, be obtained by looping with <a href="function.mysql-fetch-assoc.html" class="function">mysql_fetch_assoc()</a>.
    </p></div>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$data</span><span style="color: #007700">[]&nbsp;=&nbsp;array(</span><span style="color: #DD0000">'volume'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">67</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'edition'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">2</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$data</span><span style="color: #007700">[]&nbsp;=&nbsp;array(</span><span style="color: #DD0000">'volume'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">86</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'edition'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">1</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$data</span><span style="color: #007700">[]&nbsp;=&nbsp;array(</span><span style="color: #DD0000">'volume'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">85</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'edition'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">6</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$data</span><span style="color: #007700">[]&nbsp;=&nbsp;array(</span><span style="color: #DD0000">'volume'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">98</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'edition'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">2</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$data</span><span style="color: #007700">[]&nbsp;=&nbsp;array(</span><span style="color: #DD0000">'volume'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">86</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'edition'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">6</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$data</span><span style="color: #007700">[]&nbsp;=&nbsp;array(</span><span style="color: #DD0000">'volume'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">67</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'edition'&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">7</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>
     In this example, we will order by <var class="varname">volume</var> descending,
     <var class="varname">edition</var> ascending.
    </p></div>
    <div class="example-contents"><p>
     We have an array of rows, but <b>array_multisort()</b>
     requires an array of columns, so we use the below code to obtain the
     columns, then perform the sorting.
    </p></div>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br /></span><span style="color: #FF8000">//&nbsp;Obtain&nbsp;a&nbsp;list&nbsp;of&nbsp;columns<br /></span><span style="color: #007700">foreach&nbsp;(</span><span style="color: #0000BB">$data&nbsp;</span><span style="color: #007700">as&nbsp;</span><span style="color: #0000BB">$key&nbsp;</span><span style="color: #007700">=&gt;&nbsp;</span><span style="color: #0000BB">$row</span><span style="color: #007700">)&nbsp;{<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">$volume</span><span style="color: #007700">[</span><span style="color: #0000BB">$key</span><span style="color: #007700">]&nbsp;&nbsp;=&nbsp;</span><span style="color: #0000BB">$row</span><span style="color: #007700">[</span><span style="color: #DD0000">'volume'</span><span style="color: #007700">];<br />&nbsp;&nbsp;&nbsp;&nbsp;</span><span style="color: #0000BB">$edition</span><span style="color: #007700">[</span><span style="color: #0000BB">$key</span><span style="color: #007700">]&nbsp;=&nbsp;</span><span style="color: #0000BB">$row</span><span style="color: #007700">[</span><span style="color: #DD0000">'edition'</span><span style="color: #007700">];<br />}<br /><br /></span><span style="color: #FF8000">//&nbsp;Sort&nbsp;the&nbsp;data&nbsp;with&nbsp;volume&nbsp;descending,&nbsp;edition&nbsp;ascending<br />//&nbsp;Add&nbsp;$data&nbsp;as&nbsp;the&nbsp;last&nbsp;parameter,&nbsp;to&nbsp;sort&nbsp;by&nbsp;the&nbsp;common&nbsp;key<br /></span><span style="color: #0000BB">array_multisort</span><span style="color: #007700">(</span><span style="color: #0000BB">$volume</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">SORT_DESC</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$edition</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">SORT_ASC</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$data</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>
     The dataset is now sorted, and will look like this:
    </p></div>
    <div class="example-contents"><pre>
<div class="cdata"><pre>
volume | edition
-------+--------
    98 |       2
    86 |       1
    86 |       6
    85 |       6
    67 |       2
    67 |       7
</pre></div>
    </pre></div>
   </div>
  </p>
  <p class="para">
   <div class="example">
    <p><b>Example #4 Case insensitive sorting</b></p>
    <div class="example-contents"><p>
     Both <b><tt>SORT_STRING</tt></b> and
     <b><tt>SORT_REGULAR</tt></b> are case sensitive, strings
     starting with a capital letter will come before strings starting
     with a lowercase letter.
    </p></div>
    <div class="example-contents"><p>
     To perform a case insensitive search, force the sorting order to be
     determined by a lowercase copy of the original array.
    </p></div>
    <div class="example-contents">
<div class="phpcode"><code><span style="color: #000000">
<span style="color: #0000BB">&lt;?php<br />$array&nbsp;</span><span style="color: #007700">=&nbsp;array(</span><span style="color: #DD0000">'Alpha'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'atomic'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'Beta'</span><span style="color: #007700">,&nbsp;</span><span style="color: #DD0000">'bank'</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">$array_lowercase&nbsp;</span><span style="color: #007700">=&nbsp;</span><span style="color: #0000BB">array_map</span><span style="color: #007700">(</span><span style="color: #DD0000">'strtolower'</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$array</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">array_multisort</span><span style="color: #007700">(</span><span style="color: #0000BB">$array_lowercase</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">SORT_ASC</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">SORT_STRING</span><span style="color: #007700">,&nbsp;</span><span style="color: #0000BB">$array</span><span style="color: #007700">);<br /><br /></span><span style="color: #0000BB">print_r</span><span style="color: #007700">(</span><span style="color: #0000BB">$array</span><span style="color: #007700">);<br /></span><span style="color: #0000BB">?&gt;</span>
</span>
</code></div>
    </div>

    <div class="example-contents"><p>The above example will output:</p></div>
    <div class="example-contents"><pre>
<div class="cdata"><pre>
Array
(
    [0] =&gt; Alpha
    [1] =&gt; atomic
    [2] =&gt; bank
    [3] =&gt; Beta
)
</pre></div>
    </pre></div>
   </div>
  </p>
 </div>

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