Javascript checkbox onChange
function calc(){ if (document.getElementById('xxx').checked) { document.getElementById('totalCost').value = 10; } else { calculate(); }}HTML
<input type="checkbox" id="xxx" name="xxx" onclick="calc();"/>
Pure javascript:
const checkbox = document.getElementById('myCheckbox')checkbox.addEventListener('change', (event) => { if (event.currentTarget.checked) { alert('checked'); } else { alert('not checked'); }})My Checkbox: <input id="myCheckbox" type="checkbox" />
If you are using jQuery.. then I can suggest the following: NOTE: I made some assumption here
$('#my_checkbox').click(function(){ if($(this).is(':checked')){ $('input[name="totalCost"]').val(10); } else { calculate(); }});