Hi

I have a form giving users the option of selecting which class they want, the problem I have is that some classes last 60mins and some last 30mins, so the user could if they wish attend two 30min classes but only one 60min class, what I want to do is to ensure that if a 60 min class is picked they cannot then select a 30min class as well

I include the code for the form below

PHP Code:
<table width="1200" border="0" cellpadding="0" cellspacing="0" class="tableclass">
  <
tr>
    <
td width="110">Session1a</td>
    <
td width="110">Session2</td>
    <
td width="110">Session3</td>
    <
td width="110">Session4a</td>
    <
td width="110">Session5a</td>
    <
td width="110">Session6a</td>
    <
td width="110">Session7a</td>
    <
td width="110">Session8</td>
    <
td width="110">Session9</td>
    <
td width="110">Session10</td>
  </
tr>
  <
tr>
    <
td><input name="d1ws1" type="radio" value="ws1a" />
      
30 Mins</td>
    <
td><input name="d1ws1" type="radio" value="ws1b" />
      
60 Mins</td>
    <
td><input name="d1ws1" type="radio" value="ws1c" />
      
60 Mins</td>
    <
td><input name="d1ws1" type="radio" value="ws1d" />
      
30 Mins</td>
    <
td><input name="d1ws1" type="radio" value="ws1e" />
      
30 Mins</td>
    <
td><input name="d1ws1" type="radio" value="ws1f" />
      
30 Mins</td>
    <
td><input name="d1ws1" type="radio" value="ws1g" />
      
30 Mins</td>
    <
td><input name="d1ws1" type="radio" value="ws1h" />
      
60 Mins</td>
    <
td><input name="d1ws1" type="radio" value="ws1i" />
      
60 Mins</td>
    <
td><input name="d1ws1" type="radio" value="ws1j" />
      
60 Mins</td>
  </
tr>
  <
tr>
    <
td>Session1b</td>
    <
td rowspan="2">&nbsp;</td>
    <
td rowspan="2">&nbsp;</td>
    <
td>Session4b</td>
    <
td>Session5b</td>
    <
td>Session6b</td>
    <
td>Session7b</td>
    <
td rowspan="2">&nbsp;</td>
    <
td rowspan="2">&nbsp;</td>
    <
td rowspan="2">&nbsp;</td>
  </
tr>
  <
tr>
    <
td><input name="d1ws2" type="radio" value="ws2a" />
      
30 Mins</td>
    <
td><input name="d1ws2" type="radio" value="ws2d" />
      
30 Mins</td>
    <
td><input name="d1ws2" type="radio" value="ws2e" />
      
30 Mins</td>
    <
td><input name="d1ws2" type="radio" value="ws2f" />
      
30 Mins</td>
    <
td><input name="d1ws2" type="radio" value="ws2g" />
      
30 Mins</td>
  </
tr>
</
table
Thanks John