Knockoutjs radio integer databind to check does not work

Question

check jsfiddle

<div data-bind="foreach: ids" class="">
    <label>                      
        <input type="radio"  name="someid" data-bind="value: value, checked: $root.selectedid" />
        <span data-bind="text: text"></span>
    </label>
</div>
<br/>
<input type="button" data-bind="click: test1" value="Test1"/>
<input type="button" data-bind="click: test2" value="Test2"/>
<input type="button" data-bind="click: test3" value="Test3"/>

radiodata function (text, value) {this.text = text; this.value = value; }

var viewModel = function(){
    var self = this;
    self.selectedid = ko.observable();

    self.ids = ko.observableArray([
        new radiodata('one',1),
        new radiodata('two',2),
        new radiodata('three',3)
         ]);
    self.test1 = function(){
      self.selectedid(2);//this doesnot work
    };
     self.test2 = function(){
      self.selectedid('2');//this works
    };
     self.test3 = function(){
      self.selectedid((3).toString());//this was my hack
    };
}

var model = new viewModel();
ko.applyBindings(model);

I tried radio databindfor a property checked, My json data for selectedidare integers that I tried to bind checkedfor a radio.

I have a fixed solution for this, but does anyone know why the integer databind is not working?

like where self.testXfunctions will change the radio propertychecked

self.test1 = function(){
  self.selectedid(2); //this doesnot work
};
 self.test2 = function(){
  self.selectedid('2');//this works
};
 self.test3 = function(){
  self.selectedid((3).toString()); //and this was my hack
};

any good explanation?

Answer 1

checkedValue, , checked - , . :

checkedValue, , value . , , - , (, ), , .

, , $data checkedValue.

: , .

, , , , , === == .

:

1 == "1" // true
1 === "1" // false

JavaScript ( ), - .