ko.mapping.fromJS and dependantObservables

[jeffrey...@googlemail.com]

I need to perform Crud operations in the UI, and am using knockoutjs and the mapping plugin to do it.

However when I call toJS followed by fromJS my dependant observable function gets overwritten.

Please, how do I maintain the dependant observable as a computed function through serialisation and deserialisation with the mapping plugin?

function clientViewModel() {

    var self = this;

  self.addresses = ko.observableArray();

  self.selectedAddress = ko.observable();

  self.addressForEditing = ko.observable();

  self.addAddress = function (data, e) {

    self.addressForEditing(new address());
   };

    self.addAddressSave = function (data, e) {

        var newAddress = ko.observable(new address());

        ko.mapping.fromJS(ko.mapping.toJS(self.addressForEditing), {}, newAddress)

        self.addresses.push(newAddress);

    };

    self.editAddress = function (data, e) {

        self.selectedAddress(data);

        ko.mapping.fromJS(ko.mapping.toJS(self.selectedAddress), {}, self.addressForEditing);

    };

    self.editAddressSave = function (data, e) {

        ko.mapping.fromJS(ko.mapping.toJS(self.addressForEditing), {}, self.selectedAddress);

    };

};

function address() {

  var self = this;

    self.Property = ko.observable("");

   self.Street = ko.observable("");
    self.Town = ko.observable("");

   self.Postcode = ko.observable("");

  self.Country = ko.observable("");

  

  self.FullAddress = ko.computed(function () {

        var arr = [" ", self.Property(), self.Street(), self.Town(), self.Postcode()];

        return arr.join(", ").split(" ,").join("").trim();    

    }, this);

};

When adding a new address the FullAddress is a computed function.  

However when editing an existing address the ko.mapping call transposes FullAddress to a string on addressforediting.

Any clues?

thanks

[Noirabys]

hi,

....the join() method joins the elements of an array into a string, and returns the string.

thus self.FullAddress is a string ... 

you can use a viewmodelmapping , thats the second paramter of the mapping tool

http://jsfiddle.net/beauxjames/ps75V/

if you need transactional support i would recommend an extender for example have a look at:

https://github.com/romanych/ko.editables

for simple structures its easier to initialize by construcor

function Address(data){

   var self = this;

    self.name = ko.observable(data.name);

}

you can initialize arrays:

self.addresses = ko.observableArray(ko.utils.ArrayMap(data,function(adress){ return new Address(adress); });