checkbox

[akash kadarla]

i want the code for

a an alert box should be displayed when more than one check box is selected

[Tom Blough]

If you want one and only one check box, then use radio buttons. It's better to prevent user errors than to check and notify.

Cheers,

[Eric Pascarello]

As Tom said, a radio button will only allow for one value to be selected. It would be the best route to do that.

If you still want to use a checkbox,

<script type="text/javascript">
  function CountChecks(){
    var theCount = 0;
    var theForm = document.FormName;
    for(i=0;i<theForm.elements.length;i++){
      if(theForm.elements[i].type == "checkbox"){
        if(theForm.elements[i].checked){
          theCount++;
          if(theCount>2){
            alert("Error: Too many checkboxes checked!");
            return false;
          }
        }
      }
    }
    return true;
  }
</script>

You can call this onsubmit of your form

<form name="formName" onsubmit="return CountChecks()">

Hope this helps
Eric