title: AJAX php header returning null in javascript
body: <p>I'm setting a header in php using header('page-title: "200"'), and when i try to access it in javascript, I get a null. I don't really know what code I can provide to show you, but I doubt it matters since it works fine and returns with "200" on my localhost, but doesn't work on the remote server. 
  I'm sure it's just me making a stupid mistake. 
  Thanks,
  Josh </p>
  
  <p>EDIT here's the javascript</p>
  
  <pre><code>function RequestPage(url, push){
      //load new page 
      var xhr = new XMLHttpRequest();
      xhr.onreadystatechange = function (){
          if(xhr.readyState === 4){
              content.innerHTML = xhr.responseText;
              AttachLinkClickHandlers(content);
  
              document.title = "Delivery Duck // " + xhr.getResponseHeader('Page-Title');
  
              document.body.setAttribute("class", xhr.getResponseHeader('Page-Title'));
  
              EvalScripts();
  
              if(push){
                  history.pushState(url, document.title, url);
              }
          }   
      };
  
      xhr.open('get', url, true);
      xhr.setRequestHeader("Content-Only", 1);    
      xhr.send();
  }
  </code></pre>
  
  <p>its the xhr.getResponseHeader() that fails to work on the remote server. </p>
  
  <p>The php :</p>
  
  <pre><code>$content_only = isset($_SERVER['HTTP_CONTENT_ONLY']) &amp;&amp; ($_SERVER['HTTP_CONTENT_ONLY'] == 1);
  if($content_only){
      header('Page-Title: ' . $page_title); 
  }
  </code></pre>