Selecting multiple radio buttons

Question

Alright i have a for loop in php and it generates a group of radio buttons for a person, each radio button within the group has the same name.

for ($i = 0; $i < $count; $i++) {
            echo '<tr>';
            echo '<td>' . $something[$i] . '</td>';
            echo '<td align="center"><input class="one" type="radio" name="' . $i . '" value="1"/></td>';
            echo '<td align="center"><input class="half" type="radio" name="' . $i . '" value="0.5"/></td>';
            echo '<td align="center"><input class="zero" type="radio" name="' . $i . '" value="0" checked="checked"/></td>';
            echo '<td align="center"><input class="inactive" type="radio" name="' . $i . '" value="null"/></td>';
            echo '</tr>';
        }

I want to be able to select/check all the radio buttons with the same class by clicking a link/button. the variable $count will change every few days, so i wont know the how many different radio groups there will be. I am looking for this hopefully to be in javascript

Answer 1

You can't do this. Radio button groups allow a single selection. You will need checkboxes to accomplish this.

Answer 2

Provided the class names are unique to the radio buttons, you could do this:

var radios = document.getElementsByTagName("INPUT");
for (var index = 0; index < radios.length; index++) {
   if (radios(index).type == "radio" && 
       radios(index).className.indexOf("one") > -1) {
      radios(index).checked = true;
   }
}

All this is probably no better than using getElementsById for each, but probably better than getElementsByClassName, which isn't universally supported, I don't think.

Answer 3

okay i got mine figured out here,

            $(document).ready(function() {

            // select all radio buttons in the "one" column (.one class)
            $('#select_all_one').click(function(){
                $("input[class=one]").each(function(){
                    this.checked = true;
                });
            });

            // select all radio buttons in the "half" column (.half class)
            $('#select_all_half').click(function(){
                $("input[class=half]").each(function(){
                    this.checked = true;
                });
            });

            // select all radio buttons in the "zero" column (.zero class)
            $('#select_all_zero').click(function(){
                $("input[class=zero]").each(function(){
                    this.checked = true;
                });
            });

            // select all radio buttons in the "inactive" column (.inactive class)
            $('#select_all_inactive').click(function(){
                $("input[class=inactive]").each(function(){
                    this.checked = true;
                });
            });


          });

and then to select all the radio i use this link <a id="select_all_one" name="select_all" value="all_one"> and change the name of the id and value to half, zero, and inactive for the respected links, everything works perfect