[RESOLVED] OOP Tutorials

[MonkeyMadness]

I have been trying to adopt OOP techniques in VB.net but admit to being stumpted.

Does anyone know if there are any good tutorials out there that will walk me through all th basic principles.

However hard I try I just cant get it, but I appreciate that to improve as a developer I need to master these techniques.

Thanks

[Pirate]

No , get a book something like this one : http://www.amazon.com/exec/obidos/tg...61749?v=glance

[Edneeis]

Or try asking more specific questions, What don't you get? What have you done to try? What makes you think you haven't succeed? The biggest thing about OOP is to make and not over do it just make sure all the structure makes sense.

[Andy]

I have a similar problem. My obstacles are using the msdn and knowing what namespaces are. (not to mention knowing what to look up! )

I know what methods and properties and events are.

When the object has more than two "dots", I get lost. what exactly is this called?

These are just a FEW of the questions I have. but I'm sure this will get me in the right direction.

[Edneeis]

Whats the question exactly? Whats a namespace? A namespace is a way to categorize related objects. The namespace is like the path to the object. Using the imports statement is like making an implied shortcut to shorten the path for the reminder of that section.

[Andy]

I see. You could type in the namespace everytime you need it OR you could use it at the head of the code, right?

Here's another one: what does this statement mean?

Dim dir As New DirectoryInfo(ListBox1.SelectedItem.ToString)
            Dim fiTemp As FileInfo
            Dim fil As FileInfo() = dir.GetFiles()
            For Each fiTemp In fil

here's what I DO know:

dim dir as declares a variable named dir
AS NEW sets it to an instance of the object DIRECTORYINFO and the (listbox1.selecteditem.tostring) is a property of that object. Am I right so far?

dim fiTemp as fileinfo instantiates a variable named fiTemp as an object called fileinfo. Since fileinfo is an object already, it INHERITS the properties and methods of it. Right so far? one question about this though. Why don't I have to say DIM FITEMP AS NEW FILEINFO? like the previous statement?

and the dim fil as fileinfo()...same question...why is there no AS NEW statement? and why in this statement are there parentheses after fileinfo and not in the statement before it? Then, there is the "=" sign. I'm assuming this sets the variable "fil" as an object of fileinfo and then sets it to another object of dir.getfiles. BUT dir was instatiated earlier as directory info so dir.getfiles is a method of the object "dir" ? Right? Why then, must we set so many variable?

Am I over-analyzing this or is there some logic I'm missing?

[Pirate]

Did you try to read a book or even a tutorial that explain how OOP work in .NET ? after reading that , I'm sure you'll answer all these questions yourself and give a good logical explanation . OOP is more than the 'New' keyword . So , don't waste your time and start from now .

[nemaroller]

Originally posted by thephantom

Here's another one: what does this statement mean?

Dim dir As New DirectoryInfo(ListBox1.SelectedItem.ToString)
            Dim fiTemp As FileInfo
            Dim fil As FileInfo() = dir.GetFiles()
            For Each fiTemp In fil

here's what I DO know:

dim dir as declares a variable named dir
AS NEW sets it to an instance of the object DIRECTORYINFO and the (listbox1.selecteditem.tostring) is a property of that object. Am I right so far? Mostly, but listbox1.selecteditem.tostring is just a value that you are passing to the DirectoryInfo method that constructs an instance of DirectyInfo.


dim fiTemp as fileinfo instantiates a variable named fiTemp as an object called fileinfo. Since fileinfo is an object already, it INHERITS the properties and methods of it. Right so far? one question about this though. Why don't I have to say DIM FITEMP AS NEW FILEINFO? like the previous statement?
You aren't creating an instance of the object, just a reference, so the compiler KNOWS about the type of object fiTemp is (will be) referring to.

and the dim fil as fileinfo()...same question...why is there no AS NEW statement? and why in this statement are there parentheses after fileinfo and not in the statement before it? Then, there is the "=" sign. I'm assuming this sets the variable "fil" as an object of fileinfo and then sets it to another object of dir.getfiles. BUT dir was instatiated earlier as directory info so dir.getfiles is a method of the object "dir" ? Right? Why then, must we set so many variable?
Again, you are creating a reference, and then setting that reference equal to an already existing value, which is dir.GetFiles(). Most strict languages requires parantheses, in VB you may find if you type dim fil as fileinfo = new dir.getfiles, you get the same result. The For Each means for each object in fil, if the type of the object is fiTemp...

Am I over-analyzing this or is there some logic I'm missing?
When you say Dim X As Porsche. You have created a reference of a porsche object.
But the object does not exist yet though.
Not until you say X=New Porsche, or X = Y (some other porsche), is there actually an object being referred to.

[Andy]

Originally posted by Pirate
Did you try to read a book or even a tutorial that explain how OOP work in .NET ? after reading that , I'm sure you'll answer all these questions yourself and give a good logical explanation . OOP is more than the 'New' keyword . So , don't waste your time and start from now .

I JUST ordered that book you suggested above. Really, I think if I get the proper ground work laid out, the rest is downhill. I have James Foxall's book on vb 2003 and he talks about oop but I didn't really get it. Maybe it's just because I am overthinking it or maybe because it's just one authors explanation. I am the kink of person who likes to gleen off of all sorts of people. I'm not a slow learner but I ain't the fastest either!!

What did you mean by don't waste my time and start from now?

[Pirate]

Well , it's just an advice from someone who really wants to help . I meant you buy a book and go through it and do all the exercises (if there are any) , setp by step , understand why you do this and not that . I said that because you'll spend some time to get it and be fully OO programmer . Don't take it offense , it's all about help . I've read a lot of books but at the end I realized that MS's books are good because they talk about some specific things that other books never mention . I don't know if you are like me , when I want to do something I say "I'll do it now" . Goodluck

[nemaroller]

As pirate said, MS press books are usually the most detailed. Programming Visual Basic .Net by MSPRESS is a great start.

http://www.amazon.com/exec/obidos/tg...glance&s=books

[Andy]

Originally posted by Pirate
Well , it's just an advice from someone who really wants to help . I meant you buy a book and go through it and do all the exercises (if there are any) , setp by step , understand why you do this and not that . I said that because you'll spend some time to get it and be fully OO programmer . Don't take it offense , it's all about help . I've read a lot of books but at the end I realized that MS's books are good because they talk about some specific things that other books never mention . I don't know if you are like me , when I want to do something I say "I'll do it now" . Goodluck

absolutely no offense taken It's hard sometimes to get your expressions across in plain text. lol I ordered that book and went to look at it at my local bookstore. It looks like it will be very helpful. I am re-reading James Foxall's chapters on the subject as well. What I'd REALLY like to do is find a web-site like programmers heaven and get sample code of .net stuff and pick the code apart. Can anyone list a we-site or two?

[Pirate]

Some of the best sites for VB.NET and others :
http://www.codeproject.com/
http://www.codeguru.com/
http://www.developerfusion.com/vbnet/

Everything