PHP Checkboxes won't undo disable attribute, but will uncheck - checkbox

Question

I have a few pages of long code, but I'm having difficulty getting this to work. The following script checks all and and disables all checkboxes with a certain ID using an onclick command on one main checkbox. When the user unclicks that box, the checkmarks disappear, but remain disabled. Even if they hit the reset button, the disabled boxes stay.
Javascript:
<script>
function checkAllbase(bx) {
var cbs = document.getElementsByTagName('input');
for(var i=0; i < cbs.length; i++) {
if(cbs[i].id == '1') {
cbs[i].checked = bx.checked;
cbs[i].disabled=true;
}
}
}
</script>

Answer 1

Give each checkbox input that is associated with a package a similar name or class. Without seeing your actual html, supplying sample html below
HTML
<input type="checkbox" class="package1" name="package1[]" value="vacation">
<input type="checkbox" class="package1" name="package1[]" value="bonus">
<input type="checkbox" class="package1" name="package1[]" value="fries">
JS
function togglePackage(isChecked,packageName) {
//Choose one of the two below to use
//Below selects the inputs by the class name
var cbs = document.querySelectorAll("input."+packageName);
//Or Below selects the inputs by the input name
var cbs = document.querySelectorAll("input[name^="+packageName+"]");
for(var i=0; i<cbs.length; i++) {
//Since they are either checked and disabled (both true)
//or unchecked and enabled (both false) we can just use
//isChecked to set both at once.
cbs.checked = isChecked;
cbs.disabled = isChecked;
}
}
//Then somewhere call the togglePackage function
//bx here would be the main checkbox that you want to
//have toggling the other boxes, and "package1" is obviously
//the name or the class you gave the checkboxes.
togglePackage(bx.checked,"package1");

Answer 2

The elements remain disabled because the value being set is a constant (literal) true.
What you can do is copy bx.disabled throughout, as you're doing with bx.checked:
cbs[i].checked = bx.checked;
cbs[i].disabled = bx.disabled;
Or add another argument to pass the desired disabled state:
function checkAllbase(bx, disabled) {
disabled = disabled !== false; // limit to `true` or `false`, prefer `true`
// ...
cbs[i].checked = bx.checked;
cbs[i].disabled = disabled;
// ...
}
// usage
checkAllbase(bx); // disables elements
checkAllbase(bx, true); // also disables elements
checkAllbase(bx, false); // enabled elements