title: First button click to start timer, second to stop
body: <p>I'm struggling with making button first click to start a timer, second click to stop the timer and etc.</p>
  
  <p>Can anybody help me? :)</p>
  
  <pre><code>private void button7_Click(object sender, EventArgs e)
  {
      timer1.Start();
  }
  </code></pre>