knockout.js - knockout choose viewmodel depend on attribute -

i have that:

html:

<div data-bind="??? with?" id="mainitem">   <input type="text" id="mainquantity" value="12" data-bind="text: quantity"> шт   <input type="button" value="buy" data-bind="click: cartadd" data-good-id="2134" /> </div> 

script:

var mainviewmodel = function () {   var self = this;   var items = [ { id:2134, quantity: 12 }, .. ]; // data json    self.cartadd = function (data, event) {     var id = $(event.target).attr("data-good-id");     $.grep(self.items, function (i) { return i.id == id }).       each(function (i) { i.quantity++; })   } } 

so, need set viewmodel #mainitem element, viewmodel should items array, selected id, placed in "data-good-id" attribute.

my end result should be, quantity property binded #mainquantity element

thank you.

i think don't want use with binding. instead can foreach loop on items , access access cartadd function on parent context. example:

<div data-bind="foreach: items">     <input type="text" id="mainquantity" value="12" data-bind="text: quantity">     <input type="button" value="buy" data-bind="click: $parent.cartadd" data-good-id="2134" /> </div> 

excuse typo on phone. hope helps.