title: In ASP.Net, will radio buttons in the same group change Checked state automaticlly?
body: <p>There are 2 radio buttons in the same group on the page:</p>
  
  <pre><code>&lt;asp:RadioButton ID="RadioButton1" runat="server" GroupName="Group1"/&gt;
  &lt;asp:RadioButton ID="RadioButton2" runat="server" GroupName="Group1"/&gt;
  </code></pre>
  
  <p>In the code behined, I write the code to check both radio buttons:</p>
  
  <pre><code>RadioButton1.Checked = true;
  RadioButton2.Checked = true;
  </code></pre>
  
  <p>I thought the <code>RadioButton1.Checked</code> will be <code>false</code> because they are in the same group, when I check the second one, the first one will automaticlly uncheck. But actually, they are both <code>Checked=true</code>.</p>
  
  <p>In my application, there is a switch-case like this:</p>
  
  <pre><code>// Some code to check the default RadioButton
  
  switch(val){
    case 1:
      RadioButton1.Checked = true;
    case 2:
      RadioButton2.Checked = true;
  }
  </code></pre>
  
  <p>So sometimes both radio buttons' <code>Checked</code> will be true. That's odd, so I changed the code to:</p>
  
  <pre><code>switch(val){
    case 1:
      RadioButton1.Checked = true;
      RadioButton2.Checked = false;
    case 2:
      RadioButton1.Checked = false;
      RadioButton2.Checked = true;
  }
  </code></pre>
  
  <p>This works fine but what if I need add 10 more radio buttons, write a long list of =true, =false .....?</p>
  
  <p>Any ideas? Thanks!</p>