As of KnockoutJS 3.0, there’s an arrayChange subscription option on ko.observableArray. var myArray = ko.observableArray([“Alpha”, “Beta”, “Gamma”]); myArray.subscribe(function(changes) { // For this example, we’ll just print out the change info console.log(changes); }, null, “arrayChange”); myArray.push(“newitem!”); In the above callback, the changes argument will be an array of change objects like this: [ { index: 3, … Read more
Actually used this today – to unwrap the observable I had to do: <button data-bind=”attr: { id: ‘prefix_’ + $index() }”> Send </button> Hope this helps.
I know this is an old thread, but I was having the same problem and found out a much better solution that was probably added to knockout after this question was officially answered, so I’ll just leave it for people with the same problem. Currently there is no need for extenders, custom binding handlers or … Read more
ko.subscribable.fn.subscribeChanged = function (callback) { var oldValue; this.subscribe(function (_oldValue) { oldValue = _oldValue; }, this, ‘beforeChange’); this.subscribe(function (newValue) { callback(newValue, oldValue); }); }; Use the above like this: MyViewModel.MyObservableProperty.subscribeChanged(function (newValue, oldValue) { });
As of Select2 4.x, it always returns an array, even for non-multi select lists. var data = $(‘your-original-element’).select2(‘data’) alert(data[0].text); alert(data[0].id); For Select2 3.x and lower Single select: var data = $(‘your-original-element’).select2(‘data’); if(data) { alert(data.text); } Note that when there is no selection, the variable ‘data’ will be null. Multi select: var data = $(‘your-original-element’).select2(‘data’) alert(data[0].text); … Read more
It depends on the nature of your application. And, since you did not describe it in great detail, it is an impossible question to answer. I find Backbone to be the easiest, but I work in Angular all day. Performance is more up to the coder than the framework, in my opinion. Are you doing … Read more