add custom attribute jquery code example
Example 1: jquery add attribute
$('#someid').attr('name', 'value');
Example 2: custom attribute jquery selector
$("ul[data-group='Companies'] li[data-company='Microsoft']") //Get all elements with data-company="Microsoft" below "Companies"
$("ul[data-group='Companies'] li:not([data-company='Microsoft'])") //get all elements with data-company!="Microsoft" below "Companies"