title: PHP: How to sort the characters in a string?
body: <p>I have a set of strings containing characters in a PHP script, I need to sort those characters in each string.</p>
  
  <p>For example:</p>
  
  <pre><code>"bac" -&gt; "abc"
  "abc" -&gt; "abc"
  "" -&gt; ""
  "poeh" -&gt; "ehop"
  </code></pre>
  
  <p>These characters don't have accents and are all lower case. How can I perform this in PHP?</p>