向现有的javascript对象添加javascript函数

Question

I wrote a javascript function for Telerik RadTreeView as follows:

function CheckedNodeValues() {
    var checkedNodes = $(this).get_checkedNodes();
    for (var n in checkedNodes) {
        checkedNodes[n].get_value();
    }
}

I would like to be able to do myRadTreeView.CheckedNodeValues() as opposed to CheckedNodeValues(myRadTreeView);

Is there a way to add a function to a class in Javascript? I hope what I'm asking is clear, ideally, I would like extend the methods available on a class.

Answer 1

You should extend the prototype of your object, like this:

myRadTreeView.prototype.CheckedNodeValues = function () {
  // your code here
};

You can read more about the prototype concept here: http://www.javascriptkit.com/javatutors/proto.shtml or here: http://javascriptweblog.wordpress.com/2010/06/07/understanding-javascript-prototypes/

Answer 2

Absolutely:

myRadTreeView.CheckedNodeValues = function () {
      // do totally rad stuff here
};

To call it you would use:

myRadTreeView.CheckedNodeValues();

Answer 3

Something like this should do ..

   Telerik.Web.UI.RadTreeView.prototype.CheckedNodeValues = function() {
        var checkedNodes = $(this).get_checkedNodes();
        for (var n in checkedNodes) {
            checkedNodes[n].get_value();
        }
    }