change checkbox jq code example

Example 1: how to change checkbox state in jquery

$('[name="SelectedGroup"]').prop('checked', true);

Example 2: change checkbox jquery alert

$(document).ready(function() {
    //set initial state.
    $('#textbox1').val(this.checked);

    $('#checkbox1').change(function() {
        if(this.checked) {
            var returnVal = confirm("Are you sure?");
            $(this).prop("checked", returnVal);
        }
        $('#textbox1').val(this.checked);        
    });
});