Document.myform.checkbox.checked Without A Form

i know that what i mentioned on the question (above) isn't possible, but i have a problem here, i have double tripe and so on, forms inside a page, and i need to submit a form that

Solution 1:

Using jQuery, this could be done very succinctly.

// select all checked checkboxes with name attribute that starts with 'iphone'
var NewCount = $("input[name^='iphone']:checked").length;

if (NewCount > 1){
    descontox = 20/100;
    valorx = (total.value * descontox).toFixed(2);
    valor.value  = (total.value - valorx).toFixed(2);
    }

if (NewCount <= 1){
    valor.value = ("");}
}

EDIT: souza -- It appears based on your comments that you have already solved the issue by using a single form element. However, you would be wise to use a more generic approach like the one above, or the one posted by mrtsherman. Checking each individual input element by name will lead to a code maintenance nightmare.

It would require updating both the your markup and your javascript every time a new iPhone version and/or carrier, platform comes around. A more generic approach would allow you to simply add a new checkbox to the markup using the same naming convention and your javascript will simply handle it without the need to make any changes to the code.

Solution 2:

Use Jquery. Easy to use for something like this. Here is a jsfiddle with it working.

$(document).ready(function() {
   $("input:checkbox").click(function() {
      var checked = $("input:checked").length;
      alert(checked);
   });
});