JAVASCRIPT

multiple checkbox validation in jquery

function onSubmit() 
{ 
    var fields = $("input[name='list']").serializeArray(); 
    if (fields.length === 0) 
    { 
        alert('nothing selected'); 
        // cancel submit
        return false;
    } 
    else 
    { 
        alert(fields.length + " items selected"); 
    }
}

// register event on form, not submit button
$('#subscribeForm').submit(onSubmit)

//**************************************************
// HTML
<form method="POST" id="subscribeForm">
    <fieldset id="cbgroup">
        <div><input name="list" id="list0" type="checkbox"  value="newsletter0" >zero</div>
        <div><input name="list" id="list1" type="checkbox"  value="newsletter1" >one</div>
        <div><input name="list" id="list2" type="checkbox"  value="newsletter2" >two</div>
    </fieldset>
    <input name="submit" type="submit"  value="submit">
</form>

multiple checkbox jquery

//This are the list of checkbox(2 selected, 2 unselected)
<input name="numchec"  type="checkbox" value="1" checked/>
  <input name="numchec"  type="checkbox" value="2" />
  <input name="numchec"  type="checkbox" value="3" checked/>
  <input name="numchec"  type="checkbox" value="4" />
  
 //Jquery Code
 
 $(document).ready(function(){
     var data=$('input[name=numchec]:checked').map(function(err, el) {
      			return $(el).val();
  			}).get();
     alert(data)
});