html - How can I execute a javascript function when an input changes? -

i trying execute javascript function when input changes value. input changes value when other inputs clicked (those inputs increase or decrease value).

here html code:

<input type='button' value='–' class='qtyminus' field='quantity{{$accessory- >id}}' style="font-weight: bold;" />    <input id='accessory{{$i}}' onchange="updatenoaccessories({{$i}})"  type='text' name='quantity{{$accessory->id}}' value='1' class='qty' style="margin-bottom: 0px !important"/>  <input type='button' value='+' class='qtyplus' field='quantity{{$accessory-     >id}}' style="font-weight: bold;" /> 

js function:

function updatenoaccessories(i) {     var no = document.getelementbyid("accessory"+i).value;     document.getelementbyid("acc"+i).innerhtml = no + ' x'; } 

what want update js function:

<span>you chose:<i><b id="acc0"></b> items,</i><i><b id="acc1"></b>  things,</i><i><b id="acc2"></b>stuff</i></span> 

your button + , - not linked input onchange event never triggerd (maybe didn't paste part of code) , can use oninput instead of onchange.

you can fix :

<input type='button' value='–' class='qtyminus' field='quantity{{$accessory- >id}}' style="font-weight: bold;" onclick='updatevalue(-1,$i)'/>   <input id='accessory{{$i}}' oninput="updatenoaccessories({{$i}})"  type='text' name='quantity{{$accessory->id}}' value='1' class='qty' style="margin-bottom: 0px !important"/>  <input type='button' value='+' class='qtyplus' field='quantity{{$accessory-     >id}}' style="font-weight: bold;" onclick='updatevalue(+1,$i)'/> 

and js :

function updatevalue(i,id) {     var no = document.getelementbyid("accessory"+id).value;     no = no + i;     document.getelementbyid("acc"+id).innerhtml = no; }  function updatenoaccessories(i) {     var no = document.getelementbyid("accessory"+i).value;     document.getelementbyid("acc"+i).innerhtml = no + ' x'; }