Check whether all checkboxes are checked and then execute a function

Question

How could I make this code dry?

$("#btnSubmitToCheckOut").click(function(event) {
        var isSelected = [];

        $(".age_agree :checkbox").each(function() {
            if ($(this).is(":checked")) {
                isSelected.push("true");
            } else {
                isSelected.push("false");
            }
        });

        if ($.inArray("false", isSelected) < 0) {
            $(this).parents('form').submit();
        } else {
            alert('Please accept all the Terms and Conditions');
        }

    });

Answer 1

I was thinking something along these lines. The condition checks whether there are no unchecked checkboxes (length of the selection is 0) and then executes the appropriate branch.

$("#btnSubmitToCheckOut").click(function(event) {
    if ($('.age_agree input[type="checkbox"]').not(':checked').length == 0) {
        $(this).parents('form').submit();
    } else {
        alert('Please accept all the Terms and Conditions');
    }
});

Answer 2

I came up with this somewhat shorter solution.

Using an array to find out if one of the checkboxes has not been clicked is unnecessary here, as you are only interested in if all checkboxes are clicked or not. That leads to two possible solutions, one is using a booling to saving the state using a normal for loop or using an early return to break from the loop in case a checkbox that has not been clicked is found. I decided to go with the early return as it shortens the method and removes the need for the if/else construct at the end.

$("#btnSubmitToCheckOut").click(function(event) {
    var checkBoxes = $(".age_agree :checkbox")

    for(int i=0; i < checkBoxes.length; i++) {
        if (!checkBoxes[i].is(":checked")) {
           alert('Please accept all the Terms and Conditions');
           return;
        }
    };

    $(this).parents('form').submit();
});

What do you think?