how to check checkbox value in jquery code example

Example 1: How to check whether a checkbox is checked in jQuery?

//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
}

Example 2: jquery checkbox checked value

if ($('#check_id').is(":checked"))
{
  // it is checked
}

Example 3: how to check the checkbox in jquery

check all checkbox whit button

// Check #x
$( "#x" ).prop( "checked", true );
 
// Uncheck #x
$( "#x" ).prop( "checked", false );


example

      $('.checkAll').click(function () {
                if($(':checkbox').is(':checked')){
                    $(':checkbox').prop( "checked", false );
                }else{
                    $(':checkbox').prop( "checked", true );
                }
            })

Example 4: get the value of a checkbox jquery

$("input[type='checkbox']").val();
$('#check_id').val();