getElementsByName doesn't work after admin grid ajax request

Question

Im trying to get the selected checkboxs in invoice grid, which is working fine if I don't filter the grid or you can say before ajax request. After ajax request grid refreshes and also I can't get the selected/unselected checkboxs.

I can capture the click event on checkboxs but I want to get all of them to check which are checked & which aren't.

Here is my code

function getCheckedBoxes(chkboxName) {
    var checkboxes = document.getElementsByName(chkboxName);
}

Event.observe(window, 'load', function() {
    $(document).on('click', 'input[type="checkbox"]', function(event) {

          var chkStatus = getCheckedBoxes("invoice_ids");
          var checkboxesChecked = [];

          for (var i=0; i<checkboxes.length; i++) {
               if (checkboxes[i].checked) {
                    checkboxesChecked.push(checkboxes[i]);
               }
          }

          // Do other stuff after that
    });
});

Answer 1

instead of

var checkboxes = document.getElementsByName(chkboxName);

try prototype

var checkboxes =$$('#billship input[type="checkbox"][name="invoice_ids"]');

Answer 2

There is some variable scope issue in your code. Try below one its worked for me:

function getCheckedBoxes(chkboxName) {
    var checkboxes = document.getElementsByName(chkboxName);
    return checkboxes;  // You didn't return selected checkbox object to functional call
}

Event.observe(window, 'load', function() {
    $(document).on('click', 'input[type="checkbox"]', function(event) {

        var checkboxes = getCheckedBoxes("invoice_ids");    // Change your chkStatus to checkboxes OR you need to define checkboxes as global which should be used in any scope
        var checkboxesChecked = [];

        for (var i=0; i<checkboxes.length; i++) {
            if (checkboxes[i].checked) {
                checkboxesChecked.push(checkboxes[i]);
            }
        }
        console.log(checkboxesChecked);
        // Do other stuff after that
    });
});

Hope this will work.