title: PHP - Search key in associative array
body: <p>I want to find specific array key and return value. here is my code</p>
  
  <pre><code>$user_msg = "three";
  $array = array(
              'one'=&gt;"1",
              'two'=&gt;"2",
              'three'=&gt;"3"
  );
  </code></pre>
  
  <p>Can i use in_array function to find key ? I want check all array with for loop (not foreach). i tested in_array but don't work!</p>