title: Angular2 + Typescript + FileReader.onLoad = property does not exist
body: <p>I am using the <strong>FileReader Interface</strong> and it’s asynchronous method <strong>readAsText()</strong> to read a local text file, 
  After that when the <strong>onload event</strong> is called, I try to read my file, my source code is something like the following:</p>
  
  <pre><code>export class ReadFileComponent {
     text: string;
  
     readFile(): void {
       let reader=new FileReader();
       reader.onload = function(e) {
          this.text=reader.result;
       }
       reader.readAsText(file);   
     }
  }
  </code></pre>
  
  <p>compilation is failed because Property <strong>"text"</strong> does not exist on type <strong>"FileReader"</strong></p>
  
  <p>I think this is due to the EventListener interface does not accept objects , </p>
  
  <p>did someone please solve this kind of issue?</p>
  
  <p>thanks guys, </p>