Question

I’ve got a function in JS that check all my checkboxes in a form:

function CheckAll(chk){
    for (i = 0; i < chk.check.length; i++)
        if (chk.All.checked==true){
            chk.check[i].checked = true;
            chk.check[i].disabled = true;
        }
        else {
            chk.check[i].disabled = false;
            chk.check[i].checked = false;
        }
}

I’ve recently added some radio buttons to my form, and my question is: will this function activate ALL my radio buttons too (I know that only one radio button can be selected, but I’m not sure how this works in a script like that..)?

Here you can find my form code:

<form name='MyForm'>
    <b>This is my Simple Form</b></br>
    </br>
    <input type='radio' name='parameter' value='ONE' checked='checked' />ONE<br/>
    <input type='radio' name='parameter' value='TWO' />TWO<br/>
    <input type='radio' name='parameter' value='THREE' />THREE<br/>
    <input type='radio' name='parameter' value='FOUR' />FOUR<br/>
    <input type='radio' name='parameter' value='FIVE' />FIVE<br/>
    <input type='radio' name='parameter' value='SIX' />SIX<br/>
    <input type='radio' name='parameter' value='SEVEN' />SEVEN<br/>
    <script>
        document.write("</br>");
        var count
        var check_value = new Array()
        check_value[0] = "001"
        check_value[1] = "002"
        check_value[2] = "003"
        check_value[3] = "004"
        for(count in check_value){
            var checkbox = "<input type='checkbox' name='check' value='"+check_value[count]+"' />"
            document.write(checkbox + check_value[count] + "  ");
        }
        document.write("<input type='checkbox' name='All' value='All' onClick='CheckAll(document.MyForm);' /> All");
    </script>
    </br>
    </br>
    <input type=button value='Ok' onClick='foo(document.MyForm);'>
</form>

If this don’t work as I want, how can I solve it?

Answer 1

Testing is as simple as that : http://jsfiddle.net/yk9uD/

Content :

<form name='MyForm'>
    <b>This is my Simple Form</b></br>
    </br>
    <input type='radio' name='parameter' value='ONE' checked='checked' />ONE<br/>
    <input type='radio' name='parameter' value='TWO' />TWO<br/>
    <input type='radio' name='parameter' value='THREE' />THREE<br/>
    <input type='radio' name='parameter' value='FOUR' />FOUR<br/>
    <input type='radio' name='parameter' value='FIVE' />FIVE<br/>
    <input type='radio' name='parameter' value='SIX' />SIX<br/>
    <input type='radio' name='parameter' value='SEVEN' />SEVEN<br/>
    <script>
      function CheckAll(chk){
  for (i = 0; i < chk.check.length; i++) {
        if (chk.All.checked==true){
            chk.check[i].checked = true;
            chk.check[i].disabled = true;
        }
        else {
            chk.check[i].disabled = false;
            chk.check[i].checked = false;
        }
}
}
        document.write("</br>");
        var count;
        var check_value = new Array()
        check_value[0] = "001"
        check_value[1] = "002"
        check_value[2] = "003"
        check_value[3] = "004"
        for(count in check_value){
            var checkbox = "<input type='checkbox' name='check' value='"+check_value[count]+"' />"
            document.write(checkbox + check_value[count] + "  ");
        }
        document.write("<input type='checkbox' name='All' value='All' onClick='CheckAll(document.MyForm);' /> All");
    </script>
    </br>
    </br>
    <input type=button value='Ok' onClick='foo(some var);'>
</form>

And the answer to the question is : No, it won’t select all radio buttons.

The reason is that your code iterates only over inputs whose name is check :

for (i = 0; i < chk.check.length; i++) {