Javascript toggle checkbox

Question

I need to toggle all buttons with a single function. Function needs to toggle all checkboxes in the document as my checkboxes are freestanding and not part of a form.

I currently have this, but it is not working properly. I get syntax error: syntax error in my firefox console.

    checked=false;
    function checkedAll() {
        var c = new Array();
        c = doc.getElementsByTagName('input');
        if (checked == false){
            checked = true;
        }else{
            checked = false;
        }
        for (var i = 0; i < c.length; i++){
            if (c[i].type == 'checkbox'){
                c[i].checked = checked;
            }
        }
    }

How can I fix my code?

Thanks

possible duplicate of [How do I check a checkbox with jQuery or JavaScript?](http://stackoverflow.com/questions/426258/how-do-i-check-a-checkbox-with-jquery-or-javascript) — I wrestled a bear once., Oct 03 '13 at 09:24
FYI, your `if` statement can be replaced with just `checked = !checked;`. The `!` character negates your `checked` variable. If `checked` was equal to `true`, `!checked` would equal `false`. — James Donnelly, Oct 03 '13 at 09:25
the syntax error is about 'doc'; should be 'document'. c = doc.getElementsByTagName('input'); — shem86, Oct 03 '13 at 09:27

score 3 · Accepted Answer · edited Mar 17 '18 at 09:29

Two main items to refactor. First, instead of doc it must be document. Second instead of relying on a global just pass in a boolean to determine whether or not to check the checkboxes.

function checkedAll(isChecked) {
    var c = document.querySelectorAll('input[type="checkbox"]');

    for (var i = 0; i < c.length; i++){
        c[i].checked = isChecked;
    }
}

JS Fiddle: http://jsfiddle.net/Jvnfm/107/

score 1 · Answer 2 · answered Jul 05 '18 at 22:07

1

You can alternatively perform the following for each checkbox element:

    c[i].click();

This version will trigger any associated event handlers associated with that element.

answered Jul 05 '18 at 22:07

user9027325

135
2
6

bad idea if the script is being run by an onclick event – oxwilder Apr 25 '22 at 16:09

Javascript toggle checkbox

2 Answers2

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