如何使用jQuery计算复选框？

Question

I have tons of checkboxes that are either checked ( checked="checked" ) or unchecked.

I would like to get the number of all checkboxes, unchecked and checked checkboxes.

With check-box I mean <input type="checkbox" /> .

How to do it with jQuery? Thanks in advance!

Answer 1

You could do:

var numberOfChecked = $('input:checkbox:checked').length;
var totalCheckboxes = $('input:checkbox').length;
var numberNotChecked = totalCheckboxes - numberOfChecked;

EDIT

Or even simple

var numberNotChecked = $('input:checkbox:not(":checked")').length;

Answer 2

以下代码对我有用。

$('input[name="chkGender[]"]:checked').length;

Answer 3

Assume that you have a tr row with multiple checkboxes in it, and you want to count only if the first checkbox is checked.

You can do that by giving a class to the first checkbox

For example class='mycxk' and you can count that using the filter, like this

$('.mycxk').filter(':checked').length

Answer 4

There are multiple methods to do that:

Method 1:

alert($('.checkbox_class_here:checked').size());

Method 2:

alert($('input[name=checkbox_name]').attr('checked'));

Method 3:

alert($(":checkbox:checked").length);

Answer 5

You can do it by using name attibute, class, id or just universal checkbox; If you want to count only checked number of checkbox.

By the class name :

var countChk = $('checkbox.myclassboxName:checked').length;

By name attribute :

var countByName= $('checkbox[name=myAllcheckBoxName]:checked').length;

Complete code

$('checkbox.className').blur(function() {
    //count only checked checkbox 
    $('checkbox[name=myAllcheckBoxName]:checked').length;
});