Check if inputs form are empty jQuery

You can do it using simple jQuery loop.

Total code

<!DOCTYPE html>
 <html lang="en">
  <head>
   <meta charset="UTF-8">
   <title></title>
  <script type="text/javascript" src="http://code.jquery.com/jquery.min.js"></script>
  <style>
select,textarea,input[type="text"],input[type="password"],input[type="datetime"],input[type="datetime-local"],input[type="date"],input[type="month"],input[type="time"],input[type="week"],input[type="number"],input[type="email"],input[type="url"],input[type="search"],input[type="tel"],input[type="color"],.uneditable-input{display:inline-block;height:20px;padding:4px;margin-bottom:9px;font-size:13px;line-height:18px;color:#555555;}
textarea{height:auto;}
select,textarea,input[type="text"],input[type="password"],input[type="datetime"],input[type="datetime-local"],input[type="date"],input[type="month"],input[type="time"],input[type="week"],input[type="number"],input[type="email"],input[type="url"],input[type="search"],input[type="tel"],input[type="color"],.uneditable-input{background-color:#ffffff;border:1px solid #cccccc;-webkit-border-radius:3px;-moz-border-radius:3px;border-radius:3px;-webkit-box-shadow:inset 0 1px 1px rgba(0, 0, 0, 0.075);-moz-box-shadow:inset 0 1px 1px rgba(0, 0, 0, 0.075);box-shadow:inset 0 1px 1px rgba(0, 0, 0, 0.075);-webkit-transition:border linear 0.2s,box-shadow linear 0.2s;-moz-transition:border linear 0.2s,box-shadow linear 0.2s;-ms-transition:border linear 0.2s,box-shadow linear 0.2s;-o-transition:border linear 0.2s,box-shadow linear 0.2s;transition:border linear 0.2s,box-shadow linear 0.2s;}textarea:focus,input[type="text"]:focus,input[type="password"]:focus,input[type="datetime"]:focus,input[type="datetime-local"]:focus,input[type="date"]:focus,input[type="month"]:focus,input[type="time"]:focus,input[type="week"]:focus,input[type="number"]:focus,input[type="email"]:focus,input[type="url"]:focus,input[type="search"]:focus,input[type="tel"]:focus,input[type="color"]:focus,.uneditable-input:focus{border-color:rgba(82, 168, 236, 0.8);outline:0;outline:thin dotted \9;-webkit-box-shadow:inset 0 1px 1px rgba(0,0,0,.075), 0 0 8px rgba(82,168,236,.6);-moz-box-shadow:inset 0 1px 1px rgba(0,0,0,.075), 0 0 8px rgba(82,168,236,.6);box-shadow:inset 0 1px 1px rgba(0,0,0,.075), 0 0 8px rgba(82,168,236,.6);height: 20px;}
select,input[type="radio"],input[type="checkbox"]{margin:3px 0;*margin-top:0;line-height:normal;cursor:pointer;}
select,input[type="submit"],input[type="reset"],input[type="button"],input[type="radio"],input[type="checkbox"]{width:auto;}
.uneditable-textarea{width:auto;height:auto;}
#country{height: 30px;}
.highlight
{
    border: 1px solid red !important;
}
</style>
<script>
function test()
{
var isFormValid = true;

$(".bs-example input").each(function(){
    if ($.trim($(this).val()).length == 0){
        $(this).addClass("highlight");
        isFormValid = false;
        $(this).focus();
    }
    else{
        $(this).removeClass("highlight");
     }
    });

    if (!isFormValid) { 
    alert("Please fill in all the required fields (indicated by *)");
}

return isFormValid;
}   
</script>
</head>
<body>
<div class="bs-example">
<form onsubmit="return test()">
    <div class="form-group">
        <label for="inputEmail">Email</label>
        <input type="text" class="form-control" id="inputEmail" placeholder="Email">
    </div>
    <div class="form-group">
        <label for="inputPassword">Password</label>
        <input type="password" class="form-control" id="inputPassword" placeholder="Password">
    </div>
    <button type="submit" class="btn btn-primary">Login</button>
</form>
</div>
</body>
</html>

var empty = true;
$('input[type="text"]').each(function() {
   if ($(this).val() != "") {
      empty = false;
      return false;
   }
});

This should look all the input and set the empty var to false, if at least one is not empty.

EDIT:

To match the OP edit request, this can be used to filter input based on name substring.

$('input[name*="denominationcomune_"]').each(...


You could do it like this :

bool areFieldEmpty = YES;
//Label to leave the loops
outer_loop;

//For each input (except of submit) in your form
$('form input[type!=submit]').each(function(){
   //If the field's empty
   if($(this).val() != '')
   {
      //Mark it
      areFieldEmpty = NO;
      //Then leave all the loops
      break outer_loop;
   }
});

//Then test your bool