title: Cannot call method 'setData' of undefined
body: <p>EDIT 1</p>
  
  <p>Using the method dataTransfer.setData make it works !</p>
  
  <p><a href="http://jsfiddle.net/UH7Sf/1/" rel="nofollow">http://jsfiddle.net/UH7Sf/1/</a></p>
  
  <pre><code>d3.event.dataTransfer.setData('type',type);  
  </code></pre>
  
  <hr>
  
  <p>I'm facing a issue using methods setData and getData within d3.event</p>
  
  <p>I have to div with a draggable img element in the top one, and some drop capabilities on the second one.</p>
  
  <pre><code>d3.select('img').on('dragstart', function() { 
      var type = d3.select(this).attr('type');
      console.log("Drag starts with "+ type);
  d3.event.transfer.setData('type',type);    
  });
  
  d3.select('.drop').on('drop', function() {
      d3.event.preventDefault();
      var type = d3.event.transfer.getData('type');
      console.log("Drag ends with "+ type);      
  });
  
  d3.select('.drop').on('dragover', function() {
      d3.event.preventDefault();
  });
  </code></pre>
  
  <p>Here is the fiddle : <a href="http://jsfiddle.net/UH7Sf/" rel="nofollow">http://jsfiddle.net/UH7Sf/</a></p>
  
  <p>There is another solution to do this (transfering data within the drag&amp;drop) using d3 ?</p>