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How to create my work object and keep it up to date?

Let's simply say I add, edit and delete some expenses in a database. Every class that works with these expenses should work with an object which represents a particular expense. Whenever a user enters some data into a form or data gets loaded, I want this expenses to be encapsulated in an custom object that should be kept up to date. So what is the best way to create my expense object?
I thought that whenever the value of a textbox, combobox and what not changes I let the eventhandler update the corresponding property of my expense object.
My other idea was, that whenever there is work to be done on a particular expense a method is called which updates the object. I don't like this idea because it's not intuitive.
Are there better ways to archive that goal of an always up to date object?
Edit:
Sorry, I wasn't clear enough. I already use Entity Framework. For example if I load some data from a database, I get an Entity Framework Object (EFO). I want the data from that object in my own object(MOO). So I convert it to MOO. Then, when I open a Form, I want that form to display the data of MOO. When a user creates an a new expense he creates MOO. If he edits an expense, he edits MOO. When I pass MOO to my DataAdapterClass for upload, then it gets converted back to an EFO. This is what I want.

So are you specifically asking about how to keep your "MOO" updated based on what is happening in the UI?
If you use WPF, this is basically what you'd use databinding for - you would bind your controls to MOO properties and let the bindings keep the two in sync.

What you are looking for is a mapper between your C# code and the database retrieval/inserting functionality that does the mapping to and from objects.
I recommend using Entity Framework for this as this is the industry standard provided by Microsoft:
https://msdn.microsoft.com/en-gb/data/ef.aspx

Is it possible to "inject" updates into a Knockout ViewModel?

I'm currently looking for a solution to my issue: In our ASP.NET MVC application there are pages that are used for realtime data visualization of industrial devices. When the page gets loaded, a loading icon is shown while I fetch the viewmodel data with the current values for all the datapoints from a database. That works quite well, but it is static, by which I mean that the values don't change on the page after it finished loading. The web application itself uses a TCP listener that receives messages with values from the devices. These messages (which basically consist of a device id, a datapoint id and the value) don't arrive in fixed intervals but event-based, e.g. when a temperature value changes 0.5 K up or down.
On my page I have some graphical widgets like gauges and many other elements that correctly show the values from the initial data that gets loaded on the page load. They are bound to the Knockout viewmodel.
The problem is this: whenever a new value arrives on the server, I want to show it on the page without the need for a reload. I definitely don't want to re-transmit the whole viewmodel with some hundred datapoints on every message that arrives on the server (appr. 1 to 15 per second). In order to achieve that, I implemented the SignalR framework, which really works great. With that mechanism I now receive the new value in the client window (that means, I receive it in Javascript and now have a value object like described below).
What I need now is this: as every viewmodel gets built dynamically, they are all different. The object and properties tree is not the same for two devices, so each of them can have varying levels of subobjects. The only thing that is the same is the structure of the object that actually holds the value for each datapoint: it always consists of the aforementioned device id, the datapoint id and the value.
I need a way to update the double-type value inside the value object within the viewmodel whose device id and datapoint id match the newly arrived value message (that also consists of these two address-like ID's and the value).
I hope I got the idea across. Is there a way to do this? What would be the best practice for such a mechanism? I recently switched to Knockout-MVC (kMVC nuget package), but I'd also go back to "pure" Knockout.js and some additional scripting if that helps.
Thanks for your help and recommendations!

http://nthdegree.azurewebsites.net/mvvm-2/
Here is an article speaking to the Knockout mapping plugin
The general idea is that you should have your view model code which loads your model.
You would bind up your view model which will have a property you load from the server with an ajax call (see bottom of article).
You then just update the model with the result with
ko.mapping.fromJS(newData, mapping, modelToUpdate)
var mapping = {}; //define your mapping (see documentation or blog post)
function ViewModel(){
var self = this;
self.model = ko.mapping.fromJS({}, mapping);
self.hub = $.connection.myHub();
self.hub.client.updateModel = function(data){
ko.mapping.fromJS(data, mapping, self.model);
};
self.hub.start().done(function(){
//you could either make a call or have the "OnConnected" method trigger an 'updateModel'
});
}

ViewModel properties when linked to a DOM element allows editing which is actually updating the data in the KO observable array. Is it possible for you to change the "graphical widget"'s value (assuming that it is using some property to maintain height and width) using the IDs which you said are consistent?
I have not tested; the other option is to use KO foreach loop and update the related value.

Structural change in an Asp.Net MVC application backed by sprocs

Hello fellow developers.
First of all I apologize beforehand for the wall of text that follows, but after a day going crazy on this, I need to call for help.
I've stumbled across a problem I cannot seem to solve. I'll try to describe the scenario in the best possible way.
Task at hand: in an existing Asp.Net Mvc application, create a lookup table for an integer field, and use the textual value from the lookup in the editing view. When saving, we must first check if the lookup already has a corresponding text value for the same Root ID. If there is, use that. Otherwise, create it and then use it.
The structure:
The data model is a graph of objects where we have the root object, a collection of level A child objects, and every level A child object has a collection of level B child objects, so something like this:
Root (with fields)
Level A child (with fields) x n
Level B child (with fields) x n
The field we have to handle is on the LevelB objects.
There is a single Mvc view that handles the whole data. For collection objects, all fields are named like levelA1levelB1MyField, levelA1levelB2MyField, etc so every single field has unique name during the post. When the post happens, all values are read through a formCollection parameter which has average 120/130 keys. The keys are isolated by splitting them and looping on the numerical part of the names, values are read and parsed to the expected types and assigned to the object graph.
The datalayer part backing the object graph is all stored procedures, and all the mapping (both object to sproc and sproc to object) is hand written. There's a single stored procedure for the read part, which gets multiple datasets, and the method calling it reads the datasets and creates the object graph.
For the saving, there are multiple sprocs, mainly a "CreateRoot" and "UpdateRoot". When the code has to perform such tasks, the following happens:
For create scenario, "CreateRoot" is called, then the sprocs "CreateLevelA" and "CreateLevelB" are called in loop for each element in the graph;
For update scenario, "UpdateRoot" is called, which internally deletes all "LevelA" and "LevelB" items, then the code recreates them calling the aforementioned sprocs in loop.
Last useful piece of information is that the "business objects graph" is used directly as a viewmodel in the view, instead of being mapped to a plain "html friendly" viewmodel. This is maybe what is causing me the most trouble.
So now the textbox on the view handles an "integer" field. That field must now accept a string. The field on LevelB must remain an integer, only with a lookup table (with FK of course) and the text field from the lookup must be used.
The approaches I tried with no success:
My first thought was to change the datatype on the property MyField from integer to string on the object, then change the sprocs accordingly and handle the join at sproc level: I'd have a consistent object for my view, and the read/write sprocs could translate from string to integer and viceversa, but I can't do that because the join keys to retrieve the integer when writing are part of the Root item (as I stated in the first lines of this wall of text), which I don't know in the CreateLevelB sproc, and changing the whole chain of calls to pass those parameters would have a huge impact on the rest of the application, so no good.
My next try was to keep things "as they are" and call some "translation methods": when reading, pass the integer to the view, and there call the translation method to display the text value. When saving, use the posted text to retrieve the integer. The save part would work, I'd have all the parameters I need, but for the read part, I'd have to instantiate the "data access layer" and call its method at View level, and there's no need to explain why that is a very bad choice, so I ruled this out too.
Now I'm out of options (or ideas anyway). Any suggestion to solve this is very welcome, and also if something is not clear enough just point it out and I will edit my post with more accurate information.
Thanks.

This is not a real answer but you could rip out all sprocs and use the updating facilities of an OR mapper. This will resolve all the layering issues. You just update data how you see fit and submit at the end.
I guess this would also make the questions around "should I use an int or a string" go away.
Edit: After reading your comment I thought of the following: Do not implement alternative 1. You rather want to sacrifice code quality in the view than in the data storage model. The last one is more important and more centrally used.
I would not be too concerned with messing up the view by calling the DAL from it or the like. Changes in a view are localized and do not mess up the application's architecture. They just degrade the view.
Maybe you could create a view model in your controller and do the translations between DAL-model and view model? Or is that pattern not allowed?

How to enable edition of a list inside another object in ASP.NET MVC 2

I'm pretty new to MVC2 and need some help on how to do something. I have a Business Object which has associated a list of childs (example, A class populated with alumns). The thing is, any class can have an arbitrary number of alumns, so, how can I practically put that into a view? How will the user add new alumns or delete existing alumns to the class object, which is the one being edited?
I hope I made myself clear. Sorry no code at the moment since I still have to put up the data model and build the model objects, and then after this I'll write the Controller and the View.
Thanks!

If you're working with a collection/list of alumns then you will need to iterate over them in the view. This will enable a dynamic number of them being displayed.
Adding new ones will require calling an add action with the parent id on which it is to relate to. Similarly with delete you will need the associated id of the alumn and the parent id.
This answer from another questions with child/parent relations explains more with code.
Hope this helps

Using ASP.NET Repeaters with Object Properties

I'm trying to use ASP.NET's Repeater objects to loop over properties of an object.
For example... I have an ObjectDataSource to grab object "Program" by ID...
Program has properties such as Program.Stakeholders and Program.Outcomes which are Lists of "Stakeholder" and "Outcome" objects.
Now... what I'd really like to do is use the Repeaters to target these Properties and loop over the lists they contain. However, as far as I know I'd have to set up a separate data source for each one, tied to an individual method to retrieve each list.
Can anyone provide a better way to use these Repeater objects, or point me at some resources which would help? If this doesn't make sense I can try to clarify it more.

Using the built-in ObjectDataSource mapping up a separate datasource for each item is probably the only straightforward way (and the only way that's easy enough to be worth the effort...).
Is it a requirement that you use the ObjectDataSource, or can you choose a different way to get the data from the storage? I would recommend either using Entity Framework (which imho rocks) or creating your own custom types to which you get the data with a custom designed DAL (which is a lot more work than using EF, but if you're, like some, concerned that EF is still in infancy this might be your option).
In either case, you'll end up with a C# class called Program, which has properties of type IEnumerable<Stakeholder> and IEnumerable<Outcome> called Stakeholders and Outcomes respectively. You can then use these as datasources for the item repeaters and set them in the ItemDataBound event of the ProgramRepeater, maybe something like this:
protected void ProgramRepeater_ItemDataBound(object sender, ItemDataBoundEvent e) {
Program dataItem = (Program)e.DataItem;
Repeater stakeholderRptr = (Repeater)e.Item.FindControl("ProgramRepeater");
Repeater outecomeRptr = (Repeater)e.Item.FindControl("OutcomeRepeater");
stakeholderRptr.DataSource = dataItem.Stakeholders;
stakeholderRptr.DataBind();
outecomeRptr.DataSource = dataItem.Outcomes;
outecomeRptr.DataBind();
}
This is assuming that you're using ASP.Net WebForms, of course. In ASP.Net MVC it is even easier - you just send the Program object to the View as the Model object, and loop through its Stakeholders and Outcomes in a couple of nested for loops directly on the View.
Note: All code is provided as is, and I do not guarantee that it will run as expected or even compile. It is just to give you an idea of what to make your code do - not necessarily the exact code you need to solve your problem.