validation help - using class to make sure one or more of 6 check boxes are clicked

Im totally new at all this a开发者_StackOverflow社区nd i am trying to do something new to my website (maybe i should pay someone to do it but im trying to learn)

I have had my website created by someone and dont wish to pay them anymore. Basically my form is located here: http://www.eatatmenzies.com.au/sign-up.html

and what i would like to do is make it so one or more of the semester one and semester two checkboxes and checked. Is this something i can do in dreamweaver? I read that i would need to create a group (using the name) however the guuy who built my site has named all my checkboxes and when i change it to make a group the additions dont work anymore, so i created a class called "onerequired". but i still cant get it to work.

any help or being pointed in the right direction would be greatly appreciated.

My answer to this post might be helpful to you, the only difference is here you have to place check script on multiple checkboxes.

The thing you have to do is to just disable your Meal plan Registration button and only enable the button checking the conditions, onclick of any checkboxes.

Optionally in your script function totalcalc() you can check the checkbox value and place required alert returning false.

if(!document.getElementById('chk1').checked or !document.getElementById('chk2').checked or !document.getElementById('chk3').checked){
    alert('Please select atleast one meal');
    return false;
  }