title: Why is my json response a page full of source code
body: <p>I have a simple checkbox, on click it sends XHR to PHP page , php processes correctly and I use <code>json_encode($response)</code> to return. But instead of a simple true or false I get the source code for the page and it is causing  a "parsererror" of course.
  ajax call as follows</p>
  
  <pre><code>$.ajax({
  type: "post",
  url: "myprocessor.php",
  dataType: 'json',
  data: { "id" : idnumber, "action": "makeLive", "isLive" : "1" },
  beforeSend: function(data) {
              $("#ajaxInProgress").addClass('progress');
          },
          success: function(data) {
              $("#status").removeClass().addClass((data.error === true) ? 'error' : 'success').text('Success! Appraiser is NO LONGER Live ').slideDown('slow');
          },
          error: function(data) {
              $("#status").removeClass().addClass('error').text(' - Changing the Live status for this appraiser to "Not Live" has failed - APPRAISER IS STILL LIVE IN SYSTEM, please try again').slideDown('slow');
          },
  
          complete: function(data) {
              $("#ajaxInProgress").removeClass('progress');
              setTimeout(function() {
                  $("#status").slideUp('slow').removeClass();
              },2000);
          }
      }); 
  </code></pre>
  
  <p>The php I post to is as follows:</p>
  
  <pre><code>if (isset($_POST['action'])) { 
  if($_POST['action']=='makeLive') { 
      $checkappraiser=mysql_query("SELECT * FROM table WHERE id='".mysql_real_escape_string($_POST['id'])."'");
      if (mysql_numrows($checkappraiser)&gt;0) {
          $livesetting=mysql_result($checkappraiser,0,"live");
          $livesetting=!$livesetting;
          $runSql = mysql_query("UPDATE table SET live='$livesetting' WHERE id='".mysql_real_escape_string($_POST['id'])."'");
          if(!$runSql) {
              $return['error'] = true;
          } else { 
              $return['error'] = false;   
          }
      }
  }   
  echo json_encode($return);
  }
  </code></pre>
  
  <p>Any suggestions would be great.
  I am getting the proper data passed
  I am getting the correct data updated in DB
  My response is coming back as a parser error because it is trying to parse the source code as a json array.</p>