how to check checkbox is checked 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 if checkbox checked

$( "SELECTOR" ).attr( "checked" )  // Returns ‘true’ if present on the element, returns undefined if not present
$( "SELECTOR" ).prop( "checked" ) // Returns true if checked, false if unchecked.
$( "SELECTOR" ).is( ":checked" ) // Returns true if checked, false if unchecked.

Example 3: jquery checkbox checked

$("checkbox").is(":checked")

Example 4: jquery in checkbox checked

// Check a checkbox
$(selector).prop('checked', true);
// Un-check a checkbox
$(selector).prop('checked', false);
// Determine if checked or not
isChecked = $(selector).prop('checked');

Example 5: jquery check if checkbox is checked

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

Example 6: 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 );
                }
            })