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Jacob, there is nothing wrong with using inheritance. This is one of the pillars of OOD/OOP. Through inheritance, you also get polymorphism, one of the other pillars. You want to use an interface vs. a base class. An interface is a "base class" in theory, but has no definition. Rather it is a contract. The interface you derive your class from says that the derived class will define (host) these methods. A true base class (even abstract base class) holds common methods and data that derived base classes use. Think back to biology, when they discussed about the various classes, species, etc. of plants and animals. We all know that dogs and monkeys are types of mammals. This signifies inheritance, since mammals have certain attributes common to both dogs and monkeys. Then both dogs and monkeys have their differences. (And C# and Java can only have a single base class makes it easier.) The fact that both dogs and monkeys are mammals signifies polymorphism. This also signifies the "is a" relationship. A dog is a mammal. Therefore, the dog inherits traits and attributes (methods and data) from the mammal.
There is also the "has a" relationship where the class contains (encapsulates) a data item. Much like your Commons class contains two Task objects. A dog has four paws instead of hands and feet. Of course, these could be specialized derived objects in the base mammal object.
In the case of your Commons and Printers classes, it can stand as it is, since all it carries is data. If your properties are going to do more processing with the internally stored data, then an interface would be good if you plan to have other ways of holding your Commons data.
The main arguments for using inheritance that I have run up against is the "has a" vs. "is a" relationship. If your class "is of" another class, then use inheritance. If you class contains another class/object, then add that object as a data object.
I have also found that as I create objects/classes, sometimes I find that two or more of the objects have similar methods and data. That is a good place to use inheritance. Take the common methods and data and re-factor them into a base class and have both the old classes inherit from the base class. Also, if I find that I do need to inherit from two or more classes (as back in the old C++ days), see which one is the best choice to inherit from and encapsulate the others.
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Hi,
I'm not sure what it is you want, not even what platform you are using: DirectX, XNA, WinForms, ...?
If it is WinForms, you might want and read this little article[^].
FYI: There are quite a number of articles about games here on CodeProject.
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ok sorry, erm... what i want is to scrool the grid as the player moves from the right to the left so that the player can proceed through the level and it isn't all displayed at once
i am using winforms to make my game
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OK, read the article I provided a link to. Then whenever the grid has to move (by user action or timer), change your relevant data values and call Invalidate to get everything repainted.
If everything is linked to a grid, and only part of that is visible, have a Location variable (i.e. a Point with X and Y) that holds the distance from your grid's top left corner to your visible area's top left corner, and offset everything inside your Paint handler by that distance. Graphics.TranslateTransform() could do all that for you.
BTW: if you haven't already, I suggest you make your painting area double-buffered to reduce or avoid flicker.
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Please don't delete your questions. Now it's impossible to follow the context of this question, and it could have been something useful to others. You've been a poster long enough to know that you shouldn't be doing this.
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Yes, there already is another guy asking basically the same thing, it is a bit harder now to convince him the subject got handled here.
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how we can make an windows forms with own codes?
tanks!
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Hi,
A bit of a broad answer, but I'm having trouble trying to figure out what you're trying to do, and how.
nasis1 wrote: how we can make an windows forms with own codes?
Using Visual Studio? Start a new project of the type "Windows Application". That should open a new template for a Windows-Application, including a single form that you can edit to your liking.
If you're on a different system, or don't have Visual Studio, you'd create a new project, add the reference to "System.Windows.Forms.dll", add the "using System.Windows.Forms" on top of your file, and then you can declare new forms;
class MyForm: System.Windows.Forms.Form
{
}
static class Program
{
static void Main (String args[])
{
System.Windows.Forms.Application.Run (new MyForm);
}
}
There's a lot of information to be found on MSDN[^], if you scoll halfway the page you'll find some common walkthroughs.
Hope this helps a bit
I are Troll 
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The same way you get to Carnegie Hall.
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Take a left at Central Park 
I know the language. I've read a book. - _Madmatt
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Or was it 3 rights... I can never remembers...
I wasn't, now I am, then I won't be anymore.
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Ba-doom ching! IThankyaw!
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Write your own API and/or framework -- but I don't recommend it, I suggest you use .net instead.
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How we can make a component ?
I want to make a component whit a classlibrary not with usercontorols?
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Simply write something and call it a component.
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No, there's no reason to do that; I can create whatever I like and call it a component. I can have an enum that's a component of my Widget facility.
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hi. i can't find the index of items in CheckListBox in my program.
mean's that i write the code like this and i have access to the vales but i can not find their index.
string[] arr;
for (int i = 0; i < CheckedListbox1.Items.Count-1; i++)
{
arr[i] = serviceExtenderList.CheckedItems.ToString();
}
may i ask a little guide for that?
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To get a list of selected items in a CheckedListBox, try something like
foreach(object itemChecked in checkedListBox1.CheckedItems.
The funniest thing about this particular signature is that by the time you realise it doesn't say anything it's too late to stop reading it.
My latest tip/trick
Visit the Hindi forum here.
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Hi,
not sure what it is you are trying, however here are some ideas:
1.
you can't insert elements in an array when the array hasn't been created yet. Maybe you are missing a statement along the lines of: arr=new string[CheckedListbox1.Items.Count];
2.
I wonder why you would store a range of numbers in a string array in the first place. Strings are often abused; the general recommendation is to use actual types, not strings, where ever possible.
3.
A CheckedListbox has some properties that directly identify the checked items; see CheckedItems and CheckedIndices.
4.
Most often a generic list is a handy substitute for an array, as you don't need to set a size at the start, you can just add to it at will.
5.
If you aren't familiar with it yet, make sure you read up on the foreach statement. It works well with arrays and lists alike.
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hi,
everybody,
I would like to get source code for datagridview events.
I have already implemented with datagridview in windows application.
When user enter in datagridview's cell 2 eg, dgvSale["ItemCode"] , I want to set cursor in cell 4(4,CurrentRowIndex).
and then user entry the qty and type enter in cell(4,CurrentRowIndex). Again, I want to set cursor in cell 5(5,CurrentRowIndex)
Please let me know which event is suitable for me.
with regards,
ToeToeAung
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