使用JQuery检查所有直接子复选框上的单击父复选框

Question

I have a list in my html code where onclick of parent checkbox, the immediate child checkboxes should be checked.

<ul class="test_ex">
    <li>
        <input type="checkbox" id="chckBox" class="parent" onchange="fnTest(this);" /> <a class="ref">Fruits</a>
        <ul class="example">
            <li>
                <input type="checkbox" id="chckBox" class="child" /> <a class="ref"> Apple </a>
            </li>
            <li>
                <input type="checkbox" id="chckBox" class="child" /> <a class="ref"> Orange </a>
            </li>
        </ul>
        <ul class="test_ex_sample">
            <li>
                <input type="checkbox" id="chckBox" class="parent" onchange="fnTest(this);" /> <a class="ref">Birds</a>
                <ul class="example">
                    <li>
                        <input type="checkbox" id="chckBox" class="child" /> <a class="ref"> Peacock </a>
                    </li>
                    <li>
                        <input type="checkbox" id="chckBox" class="child" /> <a class="ref">Parrot </a>
                    </li>
                </ul>
                <ul class="example">
                    <li>
                        <input type="checkbox" id="chckBox" class="parent" onchange="fnTest(this);" /> <a class="ref"> Food </a>
                        <ul class="example">
                            <li>
                                <input type="checkbox" id="chckBox" class="child" /> <a class="ref">Bread </a>
                            </li>
                        </ul>
                    </li>
                </ul>
            </li>
        </ul>
    </li>
</ul>

I tried many ways to check only the immediate children. But none of them worked. These are few ways:

• Tried using .siblings() [Found this solution on stackoverflow only]

   function fnTest(check) { if ($(check).is(':checked')) { $(check).siblings('.example').find('.child').attr("checked", true); } else { $(check).siblings('.example').find('.child').attr("checked", false); } } 

Fiddle demo 1

Here the first list works properly. Again when clicked on second list it checks the 3rd list children too.

• Secondly tried this set of code Tried using the class which is checked annd getting children from that class. This checks all parents that belong to that class.

Fiddle demo 2

function fnTest(check) {
    if ($(check).is(':checked')) {
        var classParent = "." + $(check).attr('class');
        $(classParent).attr("checked", true);
    }
}

It would be great if someone could point out my mistake.

Answer 1

You can do this by using jQuery. First of all remove onchange="fnTest(this);" from parent checkbox. Bind change event for parent checkbox like below :

$(function(){
   $('.parent').click(function(){
      $(this).parent().find('.example:first .child').prop('checked',$(this).is(':checked'));
   });
 });

Demo

Answer 2

try

 function fnTest(check) {
      $(check).closest("ul").find(":checkbox").prop("checked",check.checked);

}

DEMO

If you want only direct children use like this

function fnTest(check) {
    $(check).closest("li").find(".example:first").find(":checkbox").prop("checked", check.checked);

}

DEMO

NOTE : use latest version in jquery, and also id should be unique

Answer 3

From your first try of using siblings(). You can change to the following:

function fnTest(check){

    if($(check).is(':checked')){
        $(check).siblings('.example:first').find('.child').prop("checked",true);
    }
    else{
        $(check).siblings('.example:first').find('.child').prop("checked",false);        
    }
      }

By using this it checks only the first children. And also change your .attr to .prop

here is a demo : Fiddle

Answer 4

// OK tested

$(document).ready(function(e) {

$('input[type=checkbox]').click(function () {
    $(this).parent().find('li input[type=checkbox]').prop('checked', $(this).is(':checked'));
    var sibs = false;
    $(this).closest('ul').children('li').each(function () {
        if($('input[type=checkbox]', this).is(':checked')) sibs=true;
    })
    $(this).parents('ul').prev().prop('checked', sibs);
});});