jQuery 1.6 未在复选框更改时将 class 添加到元素

Question

This code works fine with jQuery 1.5.1, but when I use jQuery 1.6.0 it changes the value of the checkbox after click, but it does not add the class 'done' to the element.

$("input:checkbox").live('change', function(eve) {
    eve.preventDefault();
    var el =  this.id ;
    var done =  this.done ;
    if( $(this).attr("checked") == true ) {
        $('#item-'+el).find(".text").addClass('done');
        //return false;
    }
    if( $(this).attr("checked") == false ) {
        $('#item-'+el).find(".text").removeClass('done');
        //return false;
    }

    $.post('taskDone.php', {
        id: this.id,
        value: $(this).attr("checked") ? 1 : 0
    }, function(data) {});
});

Answer 1

prior to 1.6

$(this).attr("checked") is inconsistent, as it can be a boolean or it can be a string

jQuery says something like: attribute is what's inside a property. so, it stopped sending you a bool value and it's sending you a string value instead.

if you change all

$(this).attr("checked")

to

$(this).prop("checked")

you will have no problems

---

from jQuery Documentation

For example, consider a DOM element defined by the HTML markup <input type="checkbox" checked="checked" /> , and assume it is in a JavaScript variable named elem:

elem.checked                       true (Boolean)
$(elem).prop("checked")            true (Boolean)
elem.getAttribute("checked")       "checked" (String)
$(elem).attr("checked")(1.6+)      "checked" (String)
$(elem).attr("checked")(pre-1.6)   true (Boolean)

Answer 2

Or update to version 1.6.1. The attr() function will behave as in 1.5, so you don't have to crawl through your code to find every call to attr() and decide if you need to change it to prop().