I have the below working based on the accepted answer in this question.
see this link for how this works
<form action="" name="testform" method="post" id="testform">
<div id='div_block1'>
<input type="text" value="" name="a[]" class='input_text'>
<input type="text" value="" name="b[]" class='input_text'>
<input type="text" value="" name="c[]" class='input_text'>
<select id='block1'>
<option value="" data-value=""></option>
<option value="1" data-value="11,12,13">1</option>
<option value="2" data-value="21,22,23">2</option>
<option value="3" data-value="31,32,33">3</option>
<option value="4" data-value="41,42,43">4</option>
<option value="5" data-value="51,52,53">5</option>
</select>
</div>
<div id='div_block2'>
<input type="text" value="" name="a[]" class='input_text'>
<input type="text" value="" name="b[]" class='input_text'>
<input type="text" value="" name="c[]" class='input_text'>
<select id='block2'>
<option value="" data-value=""></option>
<option value="1" data-value="11,12,13">1</option>
<option value="2" data-value="21,22,23">2</option>
<option value="3" data-value="31,32,33">3</option>
<option value="4" data-value="41,42,43">4</option>
<option value="5" data-value="51,52,53">5</option>
</select>
</div>
</form>
<script>
$(function() {
$('select').on('change', function() {
var div_id = 'div_'+$(this).attr('id');
var select_val = $(this).find('option:selected').data('value');
console.log();
if( select_val != '' ) {
var a = select_val.split(',');
$('div#'+div_id+' input[name="a[]"]').val(a[0]);
$('div#'+div_id+' input[name="b[]"]').val(a[1]);
$('div#'+div_id+' input[name="c[]"]').val(a[2]);
} else {
$('div#'+div_id+' input.input_text').val('');
}
});
});
</script>
I want to change it up slightly so that if I select 1 for example I get two values for a[], b[], c[]
I have done the below
<form action="" name="testform" method="post" id="testform">
<div id='div_block1'>
<input type="text" value="" name="a[]" class='input_text'>
<input type="text" value="" name="b[]" class='input_text'>
<input type="text" value="" name="c[]" class='input_text'>
<input type="text" value="" name="a[]" class='input_text'>
<input type="text" value="" name="b[]" class='input_text'>
<input type="text" value="" name="c[]" class='input_text'>
<select id='block1'>
<option value="" data-value=""></option>
<option value="1" data-value="11,12,13,6,12,8">1</option>
<option value="2" data-value="21,22,23,8,10,33">2</option>
<option value="3" data-value="31,32,33,2,8,6">3</option>
<option value="4" data-value="41,42,43,22,54,63">4</option>
<option value="5" data-value="51,52,53,12,34,55">5</option>
</select>
</div>
<div id='div_block2'>
<input type="text" value="" name="a[]" class='input_text'>
<input type="text" value="" name="b[]" class='input_text'>
<input type="text" value="" name="c[]" class='input_text'>
<input type="text" value="" name="a[]" class='input_text'>
<input type="text" value="" name="b[]" class='input_text'>
<input type="text" value="" name="c[]" class='input_text'>
<select id='block2'>
<option value="" data-value=""></option>
<option value="1" data-value="11,12,13,95,44,32">1</option>
<option value="2" data-value="21,22,23,12,35,51">2</option>
<option value="3" data-value="31,32,33,21,12,24">3</option>
<option value="4" data-value="41,42,43,35,52,15">4</option>
<option value="5" data-value="51,52,53,23,42,15">5</option>
</select>
</div>
</form>
see fiddle. From my understanding of how the first one worked I thought this would work however it is only taking the last value for a[], b[], c[] eg 6,12,8,6,12,8 instead of 11,12,13,6,12,8 if you select 1.
What else do I need to add to get this working as desired?