title: How can I prevent using SetPixel method?
body: <p>I have class:</p>
  
  <pre><code>class MyPic  
  {  
      private Bitmap bmp=null;
  
      public MyPic(Bitmap b)
      {
            bmp=b;
      }
  
      public Bitmap Bmp
      {
          get { return bmp; }
      }
  }
  </code></pre>
  
  <p>I made Bmp readonly property but user still can modify it by using <code>SetPixel</code> method. How can I prevent that?</p>