I am trying to use the Extensibility Method Definitions from my datacontext.designer.cs file to do some validation. So I created a new file and added this code: public partial class LawEnforcementDataContext : System.Data.Linq.DataContext { partial void InsertCourse(Course instance) // this definition copied from generated file ...
So lets say that in my entry point class (i.e the class which runs when the program starts (which has the public static void main(String args[]) function). In that class I have this variable: private ArrayList<String> myData=new ArrayList<String>(); This class instantiates another class, which needs to have access to the myData member...
I have a c# Class that has lots of virtual methods, some of these methods are essentially abstract ( they are fully implemented in subclasses and the base class is empty). To get it to compile i am throwing an InvalidOperationException in the base class with a comment on what should be done. This just feels dirty. Is there a better...
I recently expressed my view about this elsewhere* , but I think it deserves further analysis so I'm posting this as its own question. Let's say that I need to create and pass around a container in my program. I probably don't have a strong opinion about one kind of container versus another, at least at this stage, but I do pick one; fo...
I encountered this a couple of times now, and i wondered what is the OO way to solve circular references. By that i mean class A has class B as a member, and B in turn has class A as a member. One example of this would be class Person that has Person spouse as a member. Person jack = new Person("Jack"); Person jill = new Person("Jill")...
I have a data structure that I want to access / modify in different ways in different situations. I came up with this: class DataStructure { public: int getType(); private: // underlying data containers }; class WrapperBase { public: void wrap(DataStructure *input) {dataStructure = inp...
If you are passing an interface or an instance of a class as a parameter, are we passing many objects or the full vtable, because once you call a method on the instance it need to recurse the vtable and call the appropriate one right? How does this work? ...
Definition of Callback: A Function that is set as a property within a Component. And is usually called when some event occurs on the Component. For Example: If you wish to display a dialog which reads "I was clicked" when the user clicks on the Component componentB, you would write a method stored as a variable which does this: var ...
Overview: In my project, all of the UI Components that are rendered in DOM/HTML, are stored/managed as Javascript objects of type Component. Each Component Object contains a ComponentListener class which listens for events coming from the DOM/HTML rendering, and also listens for events fired to the Component that it might receive fro...
Hi all, my first time on the site so apologies if it's tagged incorrectly or been answered elsewhere... I keep running into particular situation on my current project and I was wondering how you guys would deal with it. The pattern is: a parent with a collection of children, and the parent has one or more references to particular items...
I am trying to come up with the "best" way to implement SQL Data Services flexible entity model where each class could be stored as an entity, even derrived classes. Example: Every subclass has different string Id string Kind Dictionary<string, object> Properties So far, I'm heading in the direction of having both an Entity class (wi...
The "elegant" solution to a problem I am having is to use attributes to associate a class and its properties with another's. The problem is, to convert it to the other, I'd have to use reflection. I am considering it for a server-side app that will be hosted on the cloud. I've heard many rumblings of "reflection is slow, don't use it,...
Lets take an example in C# public class Foo { public Foo() { } public Foo(int j) { } } public class Bar : Foo { } Now, All the public members of Foo is accessible in Bar except the constructor. I cannot do something like Bar bb = new Bar(1); Why the constructors are not inheritable? UPDATE I do understand we can chain...
I'm building an object to search orders in my database. There are a bunch of possible parameters that the user can set, and they can set as many as then want for each search. I've created setter methods to collect all the parameters needed for the search. My question is this. What would be "best practice" Storing the parameters, and b...
I have a PHP application where I would like to certain objects to persist in the following manner: The object must not exist in the $_SESSION. Separate web browser windows must control separate instances of the object. The end-user must not be able to modify the object by changing the content of the $_REQUEST variable by hand (if this...
Sorry for the bad question title. Let's say that I have DateRange class that basically just consists of a start date and and end date. My question is: How might I represent computed date ranges such as "This Week", "The Past Two Weeks", "Last Month", and "This Quarter", such that multiple clients can use these computed date ranges in...
What is the best practice of introducing custom (typically volatile) data into entity model classes? This may sound like a bad practice first, but it seems to be quite a common scenario. In our recent web application we have developed a proper model and in most cases we are fine with loading model entities. But there are cases where we c...
I'm using ActiveRecord to maintain information about users. The User class has the expected load(), insert(), update(), and delete() methods, setters, getters, and a few others. But I am having trouble deciding whether or not certain other methods should be included in the User class, or handled by collaborators. Here's an example: The...
I'm currently rebuilding a specialised ticket system at work (mainly used to support people with faults in remote sensing hardware...). Anyway, I was wondering whether doing lots of workflow type activity in an object's constructor is a good idea. For example, there is currently this: $ticket = new SupportTicket($customer, $title, $sta...
I've always wondered why Javascript has the global Math object instead of giving numbers their own methods. Is there a good reason for it? Also are there any drawbacks (other than efficiency) to doing something like this?: Number.prototype.round = function(){ return Math.round(this); }; Just to make clear, I understand that const...