Question

i am trying to check/uncheck all checkboxes upon clicking on select all/deselect all checkbox as follows:

onclick="selectAll(document.getElementsByName('myForm:checkboxes'));"

and the JS function:

function selectAll(checkboxes)
        {       
                for(var i in checkboxes)
                checkboxes[i].checked = true;
        }

function deselectAll(checkboxes)
            {       
                    for(var i in checkboxes)
                    checkboxes[i].checked = false;
            }

and the HTML:

<input type="checkbox" value="15" name="myForm:checkboxes" id="myForm:checkboxes3:_1">

this code works fine in firefox, but in internet explorer 9 it doesn’t work.

Answer 1

Posting comment as answer:

A for..in loop, from the documentation at Mozilla Developer Network:

A for…in loop iterates over the properties of an object in an arbitrary order

As your checkboxes are a nodeList, rather than an object, the for loop should be used instead.

So, instead of for...in, use:

for (var i=0,len=checkboxes.length;i<len;i++){
    // do stuff
}

References:

• for (){/*...*/}.
• for..in loop.