Answers for "How to get all checked checkbox value in JavaScript"

javacript is checkbox checked

//using plane javascript 
if(document.getElementById('on_or_off_checkbox').checked) {
    //I am checked
} 

//using jQuery
if($('#on_or_off_checkbox').is(':checked')){
    //I am checked
}

checked all items items in checkbox javascript

function toggle(source) {
    var checkboxes = document.querySelectorAll('input[type="checkbox"]');
    for (var i = 0; i < checkboxes.length; i++) {
        if (checkboxes[i] != source)
            checkboxes[i].checked = source.checked;
    }
}

checked all items items in checkbox javascript

$( '#container .toggle-button' ).click( function () {
    $( '#container input[type="checkbox"]' ).prop('checked', this.checked)
  })