используйте jquery для получения значений из html
$("#submit").click(function(){
var myarray = [];
$("#div input:checked").each(function() {
myarray.push($(this).val()); //push each val into the array
});
// here post Array with ajax
});
Html
<html>
<head>
</head>
<body>
<div id="div">
<input type="checkbox" value="one_name" checked>
<input type="checkbox" value="one_name1">
<input type="checkbox" value="one_name2">
<input type="button" value="submit" id="submit">
</div>
<textarea id="t"></textarea>
</body>
</html>