title: Change variable type from string to binary
body: <p>I have a string like :</p>
  
  <pre><code>  $str = "01110001";
  </code></pre>
  
  <p>and I want to change its type to binary with :</p>
  
  <pre><code>$bin = (binary) $str;
  </code></pre>
  
  <p>( because I want to inverse it ) <strong>But</strong>, when I try to <code>var_dump($bin)</code>, I get :</p>
  
  <pre><code>string(8) "01110001" 
  </code></pre>
  
  <p>Can anyone tell me what I'm missing ?</p>