return all values of input fields within div

Question

I need to form a string with the all values input fields within a div layer - using jquery

<div id="selection">
   <input class="field" id="1" type="hidden" value="A"/>
   <input class="field" id="2" type="hidden" value="B"/>
   <input class="field" id="3" type="hidden" value="C"/>
   <input class="field" id="4" type="hidden" value="D"/>
</div>

<input type="button" id="button" value="generate"/>

in this form:

id[1]=val[A]&id[2]=val[b]...so on

jquery:

 $(function() {
      $('#button').click(function() {
         //function goes here...


      });
    });

Answer 1

If you use name instead of (or in addition to) id:

<input class="field" name="1" type="hidden" value="A"/>
<input class="field" name="2" type="hidden" value="B"/>
<input class="field" name="3" type="hidden" value="C"/>
<input class="field" name="4" type="hidden" value="D"/>

you can use serialize:

$('#button').click(function() {
   alert($('#selection input').serialize());
});

which gives you

1=A&2=B&3=C&4=D

If you really want to have the id[x] structure, you can give the elements the names id[1], id[2] etc.

Edit: Oh, somehow I overlooked that you want val[x] as well. This would not be possible with serialize, only if you really put val[x] as value in the fields. But why do you need such an obfuscated structure?

---

Btw. you are missing type="button" at your button.

Answer 2

this returns all the html combined of all the inputs inside the div

var h = '';
var c = 0;
$('#selection input.field').each(function(){
 h += '&id['+(++c)+']=val['+$(this).val()+']';
});
h = h.slice(1);

alert(h);

Answer 3

<script>
    $(function() {
        $('#button').click(function() {

            var str = new Array();
            var count = 0;

            $('.field').each(
                function()
                {                   
                    str[count] = 'id['+$(this).attr('id')+']=val['+$(this).val()+']';
                    count++;
                }
            );
            alert(str.join('&'))
        });
    });
</script>
<div id="selection">
   <input class="field" id="1" type="hidden" value="A"/>
   <input class="field" id="2" type="hidden" value="B"/>
   <input class="field" id="3" type="hidden" value="C"/>
   <input class="field" id="4" type="hidden" value="D"/>
</div>
<input id="button" value="generate" type="button"/>

Answer 4

Another solution that gives the exact specified output and handles missing attributes gracefully:

See it in action at jsFiddle:

$(function() {
    $('#button').click(function() {

        var ResStr  = $('#selection input.field');

        ResStr  = ResStr.map (function () {
            var jThis   = $(this);
            var ID      = jThis.attr ("id");
            if (!ID)    ID  = "null";

            var VAL     = jThis.val ()
            if (!VAL)   VAL  = "null";

            return 'id[' + ID + ']=val[' + VAL + ']';

        } ).get () .join ('&');

        alert (ResStr);

    } );
} );