title: Retrieving ID of element on canvas
body: <p>I originally wrote a script in js that I am now rewriting using HTML5 on a canvas. Previously I had </p>
  
  <pre><code>&lt;p id = "collision"&gt;Test&lt;/p&gt;
  
  function checkHit(){
      if (my conditions) {
          document.getElementById("collision").innerHTML = "hit!";
      }
  }
  </code></pre>
  
  <p>This worked fine, but now in my canvas I have </p>
  
  <pre><code>c.fillStyle = "#ffff00";
  c.font = "30px Arial";
  c.fillText("Test", 10, 50);
  </code></pre>
  
  <p>How can I get the ID of "test" so that I can change it to "hit!" on the canvas. </p>