c# - checking returned children in knockout js -

i using knockout display items on page. have list of groups ex: group 1, group 2,... each group in it's own div. when click on 1 of groups open , display items in group. of groups don't have items display , instead of not showing change display: "no items in group"

i having trouble doing in view in javascript , thought able in knockout/jquery script

view:

<div class="accordion-group elements-by-item">         <div class="accordion-heading">             <a class="ui_title accordion-toggle text_x-large item_accordion_toggle" data-toggle="collapse" data-parent="#bytimeindex"                 data-bind="text: title() != null ? title() : identity(), attr: { 'href': '#itemcontent_' + id(), 'data-item-id': id() }">             </a>         </div>         <div class="accordion-body collapse state-loading" data-bind="attr: { 'id': 'itemcontent_' + id(), 'data-item-id': id() }">             @html.partial("_itemelements")         </div>     </div>       **_itemelements page:**      <div class="accordion-inner no_border" data-bind="foreach: children">                         <div class="element">                         ........                         </div>     <div> 

knockout/jquery js

$idx.itemsretrieved = new array();      $idx.getitemcontent = function (element) {         var _itemid = element.attr('data-item-id');         var _elementdata = $idx.itemdata;          this.getelementcontent({             groupid: _itemid,             groupdata: _elementdata.items,             elementdata: _elementdata,             apiurl: _courseindexoptions.getitemurlprefix + _itemid,             accordionbodyselector: '.accordion-body[data-item-id="' + _itemid + '"]',             accordionbtnselector: 'a[data-item-id="' + _itemid + '"]',             viewmodel: $idx.timeviewmodel         });     }      $idx.getelementcontent = function (options) {         if (linq.from($idx.itemsretrieved).any(function (x) { return x == options.groupid })) {             $(options.accordionbodyselector).removeclass(constants.stateclasses.loading);                        return;                                                                                          }          return ajax.get({             url: options.apiurl,             onsuccess: function (data) {                 var _items = linq.from(options.groupdata);                                                           var _itemtoupdate = _items.where(function (x) { return x.id == options.groupid; });                 if (_itemtoupdate.any()) {                     _itemtoupdate.first().children = data.items;                                                 }                  ko.mapping.fromjs(options.elementdata, options.viewmodel);                                          sections.elementarray.addrange(data.items);                                                       $(options.accordionbodyselector).removeclass(constants.stateclasses.loading);                        $idx.itemsretrieved.push(options.groupid);                                                        $(options.accordionbtnselector).click();                                                        }         }); 

how can check if children itemsretrieved = 0 , set message "no items" show in view page?

you can :

<div class="accordion-inner no_border" >     <div data-bind="foreach: children">         <div class="element">         </div>     </div>     <span data-bind="if : children().length == 0">no items in group</span> <div> 

i hope helps.