title: Clear image on picturebox
body: <p>How can I clear draw image on picturebox?
  The following doesn't help me:</p>
  
  <pre><code>pictbox.Image = null;
  pictbox.Invalidate();
  </code></pre>
  
  <p>Please help.</p>
  
  <p><strong>EDIT</strong></p>
  
  <pre><code>private void pictbox_Paint(object sender, PaintEventArgs e) 
  { 
       Graphics g = e.Graphics; 
       vl.Draw(g, ref tran.realListForInsert); 
  } 
  
  public void Draw(Graphics g, ref List&lt;double&gt; arr) 
  { 
      g.DrawRectangle(new Pen(Brushes.Red, 3), nodeArr[Convert.ToInt32(templstName)].pict.Location.X, nodeArr[Convert.ToInt32(templstName)].pict.Location.Y, 25, 25); 
      g.DrawRectangle(new Pen(Brushes.Green, 3), nodeArr[Convert.ToInt32(templstArgName)].pict.Location.X, nodeArr[Convert.ToInt32(templstArgName)].pict.Location.Y, 25, 25); 
      nodeArr[Convert.ToInt32(templstName)].text.Text = arr[Convert.ToInt32(templstArgName)].ToString(); 
      arr[Convert.ToInt32(templstName)] = arr[Convert.ToInt32(templstArgName)]; 
  } 
  </code></pre>