Following code works inside the onchange property of checkbox:
onchange="if(this.checked)$('#row_date').show();else $('#row_date').hide();"
but jquery
alert($('#apply_range').checked) // throw undefined, either checked or unchecked
not working.
checked is a property of the DOMElement, not a jQuery object. To get that property from the jQuery object, use prop():
console.log($('#apply_range').prop('checked'));
Or you can access the DOMElement in the jQuery object directly like this:
console.log($('#apply_range')[0].checked);
// or
console.log($('#apply_range').get(0).checked);
prop('propName') or get(0).propName your intent of getting the property value is explicit.You have to either use $('#apply_range').is(":checked") or directly access DOM element: $('#apply_range')[0].checked.
alert($('#apply_range').get(0).checked)