jQuery将2个输入框的值添加到第三个

Question

I have 3 input boxes in my page.

What I need to do is Onchange add the values of Input box A and Input Box B with a comma separating the two values.

For example:

Input A = 'MyValueA'
Input B = 'MyValueB' 

Result = 'MyValueA , MyValueB'

Answer 1

$('#inputa, #inputb').change(function (e) {
  var result = $('#inputa').val() + ", " + $('#inputb').val();
  $('#inputc').val(result);
});

Answer 2

$("#input1, #input2").bind('change', function(){
      $("#input3").val($("#input1").val() + ',' + $("#input2").val());
});

Answer 3

This will allow infinite textboxes

HTML

<input class="valuegroup" id="inputa" />
<input class="valuegroup" id="inputb" />

<input class="output" id="inputz" />

JS

$(function() {
  $('.valuegroup').on('change keyup', function() {
    var myVal, newVal = $.makeArray($('.valuegroup').map(function(){
        if (myVal = $(this).val()) {
            return(myVal);
        }
    })).join(', ');
    $('.output').val(newVal);

  });
});​

DEMO