How to operate with html radioButtons. Validation , checking if checked, collecting values?

I need help. I'm trying to make a .Net, c# application for online creating surveys. I have a few 开发者_如何学编程types of questions, and than I dynamicly put labels, combos, textboxes ... on the form. Up to this point, I somehow managed to get. Than, on click on add button, I write down the responses in html format using stringBuffer and append function. Example.

public string RetOptionalQuestion(string seq_numm, string question, string answersOpt)  
{  
       StringBuilder _output = new StringBuilder();

   _output.Append(@ " <tble><t"r"><th>" + seq_numm + "." + question + "</th></tr>");  
   _output.Append(@"<tr><td><table>");

   string[] words = answersOpt.Split(';');

    int m = 0;
    foreach (string word in words)
    {
       if (word != "") 
         {
          _output.Append(@" <tr><td> <label> " + word + "</label> </td> <td>
               <input  id='optional" + question + Convert.ToString(m) +
                    "'type='radio' name='rbOpt" + question + "' </td> ");
         m++;
         }
    }
    _output.Append("</table></td></tr></table>");
    return _output.ToString();
}

Now, I hawe to validate this questions(at least one radio checked...). They have the same name,this mean the same group, so only on e can be selected. Than I have also to save the values(responses) of this questions to the database. Problem is that I don't know how to operate with this html objects. Also how to set tehm the ID-s. I'm trying with javaScript , but with no success. Do you have any advice, hint, example, solution ... where to start... I would be very pleased Thanks, Martin

Any input controls posted to the form can be found in the Request.Form dictionary, the key is the 'Name' attribute of the input tag. (I think)

http://msdn.microsoft.com/en-us/library/ms525985(v=vs.90).aspx