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Hi all
in VFP, When I begin to work with a project, I create control that is a subclass of it is baseclass, then I code what I want to this subclass, then I drag it and put it on the form. and I use this subclass in all my forms later on.
Now to make that in vb.net I found the UserControl is the closet control to do what I want.
Q1: Is UserControl is the right direction to achieve what I want?
I have did some tests on UserControl and I have these questions
1- Why it gives warning in 'Me.Version = "1.0"
2- Why it gives warning and my vb crashes and could not be restarted unless I close all vb IDE's in Version = value
3- Should I assign a new variable (m_version) for each property I want to add? Cannot I work directly with property?
4- When I drag the control to my form, I notice that the control (Textbox) (width and height) are not expanded to take the the Length and Height of the Usercontrol. Should I handle that manually?
5- I have included many code in the Get, so I would like to know what is the best I should use.
Public Class UserControl1 ' I add Textbox
Dim m_Version
Property Version()
Get
'Version = "1.0" ' Worked Fine
'Me.Version = "1.0" ' Warning 3 Property 'Version' doesn't return a value on all code paths. A null reference exception could occur at run time when the result is used.
'Return "1.0" ' Worked Fine
Return m_Version ' Worked Fine
End Get
Set(ByVal value)
m_Version = value ' Works Fine
'Version = value ' Warning 3 Expression recursively calls the containing property 'Version'.
End Set
End Property
End Class
TIA
Like car accidents, most hardware problems are due to driver error.
Samir R. Ibrahim
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Case sensativity, Version is a property and you're using it as a variable, so Version = value wouldn't work, I'm assuming your Version property is referencing m_Version, a private variable that the property Version reflects on.
Samir Ibrahim wrote: 'Me.Version = "1.0" ' Warning 3 Property 'Version' doesn't return a value on all code paths.
will not work, nor should it, you should use
Return m_Version
which is your private variable
Consider the property Version as an interface to your m_Version variable, you do not change the Property but merely what the Property reflects.
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Thank you. Appreciated your answer.
Like car accidents, most hardware problems are due to driver error.
Samir R. Ibrahim
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Samir Ibrahim wrote: 1- Why it gives warning in 'Me.Version = "1.0"
Because the Get part of the property must return a value to the caller and your code apparently doesn't do that. Since a Version property should never be set by a caller, your code should read, as a ReadOnly property:
Public Class MyControl
Private Const m_Version As String = "1.0"
Public ReadOnly Property Version() As String
Get
Return m_Version
End Get
End Property
End Class
Seriously, pick up a beginners book on VB.NET. The problem you're having has nothing to do with subclassing or anything of the sort. You're missing a basic understanding of how Properties work.
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You know something?
It became hard for someone to ask simple question and he got an answer without the person who answer the question show his arrogance and he know to much and he reads a lot of books and all should do as he did.
well, I have something to say to you, I am not a beginner, I know classing and subclassing more than you can imagine. 6 month of learning vb.net and i finished my first sql server vb.net application and my company work on it now.
Search for "imdb dll" or "imdb.dll" in google, it is a dll based on class i create it.
I was in top contributor in many vfp forums, and i am giving help in vb.net forums as well.
It seem the person should be as***le and super arrogance in order to get some respect.
-if Return Version is wrong then this is bu***hit design
-If Every Property should be replaced by a variable, that is bu***hit design
-If creating a UserControl and put some coding in it, and then drag this Usercontrol to a form and the code written in the UserControl design being executed in the form, well if that is not subclassing I wonder what it is.
Dave Kreskowiak wrote: pick up a beginners book on VB.NET
I will follow your advice and get a beginner vb.net book plus a milk biberon
I had enough of asking help in here.
Thanks.
Like car accidents, most hardware problems are due to driver error.
Samir R. Ibrahim
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Samir Ibrahim wrote: You know something?
It became hard for someone to ask simple question and he got an answer without the person who answer the question show his arrogance and he know to much and he reads a lot of books and all should do as he did.
well, I have something to say to you, I am not a beginner, I know classing and subclassing more than you can imagine. 6 month of learning vb.net and i finished my first sql server vb.net application and my company work on it now.
Search for "imdb dll" or "imdb.dll" in google, it is a dll based on class i create it.
I was in top contributor in many vfp forums, and i am giving help in vb.net forums as well.
It seem the person should be as***le and super arrogance in order to get some respect.
 Excuse me, but where was I "super arrogant"?? I'm not out here try to grab respect. I'm out here trying to help people WHO WANT IT. IMHO, it's your response here that is "super arrogant".
I pointed out that you don't have a basic understanding of how Properties work, which is beginner-level knowledge. If you can't accept that, I'll just throw you on my blacklist of people I'll never help again.
Samir Ibrahim wrote: -if Return Version is wrong then this is bu***hit design
Excuse me, but you wrote that code, not me. If you want to say that VB.NET's syntactic requirements are bullshit, go back to writing VFP code...
Samir Ibrahim wrote: -If Every Property should be replaced by a variable, that is bu***hit design
I never said that. Every property has to support either a Gettor, a Settor, or both. Either/Both of which much be backed by a constant, a variable, or some other storage, to make the property usefull. If you understood the basics of Properties, you never would have said what you did.
Samir Ibrahim wrote: -If creating a UserControl and put some coding in it, and then drag this Usercontrol to a form and the code written in the UserControl design being executed in the form, well if that is not subclassing I wonder what it is.
I never said that wasn't subclassing. I said the problem you have in your code HAS NOTHING TO DO WITH SUBCLASSING.
Samir Ibrahim wrote: I will follow your advice and get a beginner vb.net book plus a milk biberon
I had enough of asking help in here.
Fine, I'll throw you on the blacklist then. I'm not the one being super arrogant.
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Dave Kreskowiak wrote: I'm not out here try to grab respect
Maybe/Maybe not. But you got mine.
Dave Kreskowiak wrote: I pointed out that you don't have a basic understanding of how Properties work
I know how property work and should work. I just HATE how property work in vb.net
Dave Kreskowiak wrote: Samir Ibrahim wrote:
-if Return Version is wrong then this is bu***hit design
Excuse me, but you wrote that code
Yes I write that code in my app and it gives error which is not logical error in my understanding of how PEM's should work in a class. I did not say you write that neither you mention it. That was an expression of my thought.
Dave Kreskowiak wrote: I said the problem you have in your code HAS NOTHING TO DO WITH SUBCLASSING.
What/Where is my problem in my code?
Did you notice the remark ' I put in front of the lines? did you notice the remark I put after the ' "works fine" or "gives warning", I managed to make the property work before I ask this question. I read and search google and reading in 3 books and when I sleep and I dream That I am searching google.
All I was asking is "Why it is giving warning"
It's hard to threw 15 years of "any Language" experience behind your back and start learning new language from scratch.
In my stupid mind, when you are working in class and you code Me.Version or just Version, LOGICALLY they both should point to the same property. Yes I find that not logical and has no reason to give error.
Eventually, You was right. I DON'T UNDERSTAND HOW PROPERTY WORK IN VB.NET
The capital letter is for emphasizing not shouting.
Dave Kreskowiak wrote: Excuse me, but where was I "super arrogant"??
I had one point to fix about "as***le and super arrogance"
I did not mean to say that about you, I am saying that about the Post Owner PO. although after reading my post it seems like it is towards you.
Sorry for that, A thought in mind translated in wrong way. please accept my apology.
In short, 15 years programming experience, I cannot accept "read beginner book" as an answer, but I can accept "Vb.net Work Like that either you like or no"
I am feeling nervous and upset from my self not from you.
Sorry.
Like car accidents, most hardware problems are due to driver error.
Samir R. Ibrahim
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Samir Ibrahim wrote: It's hard to threw 15 years of "any Language" experience behind your back and start learning new language from scratch
Okay Doofus, explain why, if your elite skills are so good, you are asking why writing a function (forget that it's a property for the moment) without returning a value causes a compiler warning that there is no value returned?
Let's go back to OO school:
Getter methods are used to RETURN a value without changing anything.
Setter methods are used to CHANGE a value without returning anything.
Which bit do you not understand? This is NOT VB.Net nor M$, it's first principles.
Panic, Chaos, Destruction.
My work here is done.
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williamnw wrote: you are asking why writing a function (forget that it's a property for the moment) without returning a value causes a compiler warning that there is no value returned?
Where I mention that I am not returning a value for the function? show me.
here is my question
Public Class myclass1
Function Sum()
Sum = 1 + 2 ' <-- Works Fine
Me.Sum = 1 + 2 ' <-- Gives error although me.Sum should be the same as Sum alone
End Function
End Class
Like car accidents, most hardware problems are due to driver error.
Samir R. Ibrahim
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0. No question, just a statement.
1. the first line is assigning the value that will be returned:
Samir Ibrahim wrote: Sum = 1 + 2 ' <-- Works Fine
2. The second line is trying to assign a new value to the what would be returned:
Samir Ibrahim wrote: Me.Sum = 1 + 2 ' <-- Gives error although me.Sum should be the same as Sum alone
Your whole reference point is wrong. With every post you are showing more ignorance and less ability. These are not new concepts, they have not changed for a long time. The example given, with a bit of editing, wouldn't have worked in any version of VB since classes came in in VB4
You failed to ask a very basic question. When given the best possible answer you ranted back.
In summing up My Lord, I submit that the defendant is indeed a Doofus and should be shown no mercy. The case for the prosecution rests.
Panic, Chaos, Destruction.
My work here is done.
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Public Class myclass1
' It's "best practice" to explicitly declare visibility of the Function and to
' define it's return type if you're not using LINQ, or some other technology
' that will try to imply the return type for you based on possible values that
' the code might return.
Public Function Sum() As Integer
' You haven't defined Sum anywhere, except as a function name. VB6 supported just
' treating the function name as the return value holder. You should NOT be using
' practice in VB.NET. It is only there for backward compatibility with converted
' VB6 code.
Sum = 1 + 2 ' <-- Works Fine
' Now you're treating Sum not as a variable, as in the previous line, but as an object
' or property. This will not work since Sum, outside of it's own code, cannot be
' as a variable since, in true OOP, it's a method name.
Me.Sum = 1 + 2 ' <-- Gives error although me.Sum should be the same as Sum alone
' It is considered "best practice" to explicitly declare a single Return statement.
Return x
End Function
End Class
Serisouly, VB6 and VFP have taught you some very bad habits that are not supported in the true OOP world of VB.NET. I still highly recommend picking up a book on VB.NET so you can learn how the basics are really supposed to work, instead of the garbage VFP taught you.
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Samir Ibrahim wrote: I know how property work and should work. I just HATE how property work in vb.net
I works exactly the same as it does in any .NET lanuage, be it Managed C++, C#, VB.NET, ... It's very standard and doesn't deviate from accepted norms in other languages outside the .NET environment. So, I fail to understand how you find the functionality or structure of a VB.NET Property weird.
Samir Ibrahim wrote: I cannot accept "read beginner book" as an answer
There are other uses for books like that, such as being a reference when converting code/concepts from other languages to VB.NET.
Yeah, I saw all the ' marks in your code snippet. It looked as though you were guessing, trying to figure out how properties worked. Properties are a very basic concept in .NET, so that's why the book suggestion.
The rest, I'm not going to touch.
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Samir Ibrahim wrote: I know classing and subclassing more than you can imagine
Samir Ibrahim wrote: 6 month of learning vb.net
My career is a mix of low level embedded, hardware and software overy thirty years and there is a lot I can learn from Dave.
His point was valid.
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Okay, Dave and Ellain have been nice to you. I won't be:
Your code example was sh!t. Your knowledge of OO principles is w!nk. A rabid monkey knows more than you.
Is that clear enough or do you need it carved on stone and shoved up your manky a...?
Panic, Chaos, Destruction.
My work here is done.
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Normally, When you have question in forums, and you have an answer, say it. otherwise it is much better to stay quite and play a game such Monkey Island if you love monkeys that much.
I refuse the answer of "read books" because I am reading 3, and "search google" because I do. Should I read the 550 pages of books just to know that the answer to my question is "No, That cannot be done".
I would like to know your answer about my
williamnw wrote: w!nk
OO question .
williamnw wrote: Your code example was sh!t.
That example is working fine. Make a good statement so I can comment on it.
Like car accidents, most hardware problems are due to driver error.
Samir R. Ibrahim
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*cough* name is Elliott, not Ellain *cough*
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I wouldn't call Trollslayer Elliot as she'd scratch me.
Panic, Chaos, Destruction.
My work here is done.
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Samir--
If you think Dave's answer was arrogant because of how spot on it was (meaning that it is completely correct), then I suggest you have no business getting into the programming profession. You should get involved in a touchy-feely business like fast food, or car lot boy where a lack of knowledge about your chosen profession has no bearing on your ability to excecute your professional skills.
Otherwise, suck it up and learn. This isn't a freaking prep school for pampered children.
Good luck and I wish you well.
The world is a stage and most of us are desperately unrehearsed.
—Sean O’Casey, Playwright
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Jerry Hammond wrote: If you think Dave's answer was arrogant because of how spot on it was (meaning that it is completely correct), then I suggest you have no business getting into the programming profession.
Please read my last reply to Dave, I translate an idea in my mind in wrong words.
Like car accidents, most hardware problems are due to driver error.
Samir R. Ibrahim
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Samir Ibrahim wrote: 6 month of learning vb.net
Six months of "learning VB.net" makes you a rank amateur, a newbie, a mere child. It took me ten years to get to a point where I felt comfortable in my knowledge of C++. I've been doing C# for just two years (about 7 years less than almost everyone else here), and while I feel pretty comfortable with it, I wouldn't call myself "accomplished".
And while I realize that this is the VB forum, saying you code in VB is like admitting you use AOL to get on the internet.
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001
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John Simmons / outlaw programmer wrote: saying you code in VB is like admitting you use AOL to get on the internet.
Hey now, I can understand bashing the OP, but the rest of us?
Back when <= VS6, I would agree with you; but with the CLR/CLS, does it really matter what you use to 'develop' with these days (other than fitting in with the C# norm)?
Any suggestions, ideas, or 'constructive criticism' are always welcome.
"There's no such thing as a stupid question, only stupid people." - Mr. Garrison
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Jon_Boy wrote: Hey now, I can understand bashing the OP, but the rest of us?
I am an equal-opportunity abuser.
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
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"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001
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John Simmons wrote: I am an equal-opportunity abuser.
Jon-boy lowers his head and prepares to be clubbed for his deep rooted love of VB.
Any suggestions, ideas, or 'constructive criticism' are always welcome.
"There's no such thing as a stupid question, only stupid people." - Mr. Garrison
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You have 10 years experience in C++, 2 years in C#
Since the algorithm and principals (thinking of solving the problem) is the same almost in all language.
can you compare your self for learning let say "Delphi" with someone who has no programming experience at all?
Like car accidents, most hardware problems are due to driver error.
Samir R. Ibrahim
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Samir Ibrahim wrote: You have 10 years experience in C++, 2 years in C#
No, I have 18 years in C++, 2 in C#, 8 in Pascal, and a number of years in more obscure languages on systems that were not PCs. I've been programming for a living for 30 years.
Samir Ibrahim wrote: Since the algorithm and principals (thinking of solving the problem) is the same almost in all language.
Old news - I discovered that in 1981.
Samir Ibrahim wrote: can you compare your self for learning let say "Delphi" with someone who has no programming experience at all?
Delphi is Pascal, so no, I can't compare the two since I already know Pascal.
What point are you failing to make?
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001
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