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Re: boxing and unboxing creating confusion

Malcolm Smart29-Oct-07 22:12

29-Oct-07 22:12

Sonia Gupta wrote:
class a
{
public void getdata()
{
}
}
class b
{
public void getdata()
{
}
}
main()
{
a aa;
b bb;
bb *ptr;
ptr = &bb;
ptr = &aa;
ptr->getdata();//class a getdata function
}
i was trying to call the function of class a though the object of class b.
can i do this thing using the boxing and unboxing?

Boxing and unboxing relates to linking value and reference types. It has nothing to do with pointers and references. I would take a wild guess and say you've been on some C++ sites, or talked to a C++ dev from the code above.

I think you have had a few suggestions from others here and I reiterate : GET A C# BOOK AND READ IT. Your questions are pointless, you never follow up the answers, you NEVER show any appreciation whatsoever. You just post another pointless question.

Please give us the decency of an answer to this question :-

What did you think the code you pasted above would do, or what it means? It doesn't even come anywhere near close to compiling in C#.

"More functions should disregard input values and just return 12. It would make life easier." - comment posted on WTF

"This time yesterday, I still had 24 hours to meet the deadline I've just missed today."

Re: boxing and unboxing creating confusion

Sonia Gupta29-Oct-07 22:19

Sonia Gupta

29-Oct-07 22:19

i know , i can't compile this code in c#.For the sake of simplicity , to make othes understand my question/problem , i am showing it up , in this way.If i woulf have done it in c#, i would have never asked it .Don;t u think my friend?

Soniagupta1@yahoo.co.in
Yahoo Messenger Id = soniagupta1

Re: boxing and unboxing creating confusion

Malcolm Smart29-Oct-07 22:27

Malcolm Smart

29-Oct-07 22:27

Your response makes less sense to me than your question.

You are asking a question that makes no sense to the environment you are in!

You are asking about boxing / unboxing, and showing non C# code , in a C# forum, that attempts to take references and pointers which C# doesn't (easily) do.

It is like me asking somebody on a building forum how to build a house using small angry dogs.

It doesn't make sense.

Forget the code - ask your question in as simplistic terms as you can, and also state WHY you want to know this. Then we can help.

Re: boxing and unboxing creating confusion

Andrei Ungureanu29-Oct-07 22:31

Andrei Ungureanu

29-Oct-07 22:31

Sonia Gupta wrote:
i can't compile this code in c#

Have you tried unsafe blocks?

Sonia Gupta wrote:

i was trying to call the function of class a though the object of class b.can i do this thing using the boxing and unboxing?

You can call a function of class a using an object of class b type if class a is a base class for class b.

There are 10 kinds of people: those who understand binary and those who don't

Re: boxing and unboxing creating confusion

Christian Graus29-Oct-07 23:12

Christian Graus

29-Oct-07 23:12

BUY A BOOK !!!!!!!!

Christian Graus - Microsoft MVP - C++

"also I don't think "TranslateOneToTwoBillion OneHundredAndFortySevenMillion FourHundredAndEightyThreeThousand SixHundredAndFortySeven()" is a very good choice for a function name" - SpacixOne ( offering help to someone who really needed it ) ( spaces added for the benefit of people running at < 1280x1024 )

character replace

pavya_Cool29-Oct-07 21:29

pavya_Cool

29-Oct-07 21:29

Hi to all,

I have one string "Ganges: River Of Life" & i want to replace ':' character with space. i have following code but it is not working.

str = "Ganges: River Of Life";
str.Replace(':',' ');

Anybody tell me why this happened?

Pravin

Re: character replace

Giorgi Dalakishvili29-Oct-07 21:31

Giorgi Dalakishvili

29-Oct-07 21:31

The reason is that Replace function doesn't modify its parameter, it just returns new string so your code should look like this:

str=str.Replace(':',' ');

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Re: character replace

pavya_Cool29-Oct-07 21:40

pavya_Cool

29-Oct-07 21:40

thanks Giorgi Dalakishvili,

code is working now...! thanks again.

Pravin

Re: character replace

Giorgi Dalakishvili29-Oct-07 21:42

Giorgi Dalakishvili

29-Oct-07 21:42

Glad to help you Smile | :)

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Automatic Number Plate Recognition

dims1229-Oct-07 21:09

dims12

29-Oct-07 21:09

Is it possible to develop Automatic Number Plate Recognition system in C#? Definetely yes Smile | :)

But are there some freeware computer vision libraries to do this? How many time and cost it should be?

Thanks.

Re: Automatic Number Plate Recognition

Colin Angus Mackay30-Oct-07 1:16

Colin Angus Mackay

30-Oct-07 1:16

dims12 wrote:
Is it possible to develop Automatic Number Plate Recognition system in C#? Definetely yes But are there some freeware computer vision libraries to do this? How many time and cost it should be?

Yes.

Don't know.

The hint is in the name ("freeware").

Upcoming FREE developer events:
* Glasgow: SQL Server Managed Objects AND Reporting Services ...

My website

Re: Automatic Number Plate Recognition

zain7868-Feb-10 0:22

zain786

8-Feb-10 0:22

hi there

firstly, get this open source control from here:http://www.pixel-technology.com/freeware/tessnet2/

Sample code i wrote for windows form c#: u can figure out the rest

openFileDialog1.ShowDialog();

Bitmap image = new Bitmap(openFileDialog1.FileName);
pictureBox1.Image = image;
tessnet2.Tesseract ocr = new Tesseract();
ocr.SetVariable("tessedit_char_whitelist", txtparameters.Text);
ocr.Init(@".\tessdata\", "eus", false);
List<tessnet2.Word> result = ocr.DoOCR(image, Rectangle.Empty);
foreach (tessnet2.Word word in result)

textBox1.Text += word.Text + "\r\n";

Run my Application on client side

w20929-Oct-07 20:19

w209

29-Oct-07 20:19

Hello friends
I have a Managed Application, working fine on mine system.
I want to install it on the clients machine .
and the databse is on the server so .
Do i need to make a dsn of it to connect with it.
Smile | :)

Re: Run my Application on client side

N a v a n e e t h29-Oct-07 20:31

N a v a n e e t h

29-Oct-07 20:31

w209 wrote:
Do i need to make a dsn of it to connect with it.

If your server have a static IP, you can use that

All C# applications should call Application.Quit(); in the beginning to avoid any .NET problems.- Unclyclopedia

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Re: Run my Application on client side

w20929-Oct-07 20:35

w209

29-Oct-07 20:35

it does not have a static ip

Re: Run my Application on client side

N a v a n e e t h29-Oct-07 21:11

N a v a n e e t h

29-Oct-07 21:11

AFAIK, it requires a static IP to connect. ALternatively you can create a webservice and map it with a domain name, make your application contact to this webservice, and webservice to your database which is in same server.

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drop down list post back refreshes to default state. How to prevent this?

humblepgmr29-Oct-07 19:18

humblepgmr

29-Oct-07 19:18

Hi all,
I have a dropdown list on a c# webpage.
The page allows the user to select from a dropdown.
The page allows the user to click on a submit button after selecting.

Once the user selects and presses the dropdown, the system automatically refereshes the page and refereshes the dropdown to default state which doesn't allow me to capture the dropdownllst.SelectedValue.

Kinda frustrating, Any suggestions?

Thanks

Re: drop down list post back refreshes to default state. How to prevent this?

sujithkumarsl29-Oct-07 19:23

sujithkumarsl

29-Oct-07 19:23

post this in asp.net forum

My small attempt...

Re: drop down list post back refreshes to default state. How to prevent this?

N a v a n e e t h29-Oct-07 19:47

N a v a n e e t h

29-Oct-07 19:47

humblepgmr wrote:
which doesn't allow me to capture the dropdownllst.SelectedValue.

Is viewstate disabled for your page ? Where you are trying to capture the selected item ?

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Is object value type or reference type

G.K.M.29-Oct-07 18:02

G.K.M.

29-Oct-07 18:02

hi all,

Is object value type or reference type or can be of both type !!!!

Thanks in advance.

Gaurav

Re: Is object value type or reference type

N a v a n e e t h29-Oct-07 18:57

N a v a n e e t h

29-Oct-07 18:57

It's a reference type. Value types are primitive types like int,char

All C# applications should call Application.Quit(); in the beginning to avoid any .NET problems.- Unclyclopedia

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Re: Is object value type or reference type

J4amieC29-Oct-07 23:15

J4amieC

29-Oct-07 23:15

N a v a n e e t h wrote:
Value types are primitive types like int,char

And any user defined structs.

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add dropdown list server control in classs library project

deepalititi29-Oct-07 17:59

deepalititi

29-Oct-07 17:59

hi i have created on class library project in c#.net 2.0. I want to add drop down list web server control in class library project in c#.net. But i have seen that System.Web.UI namespace is not supported in this type of project. But i have to add it anyway.

Anyone has idea or code to implement this.

Please help me out.

Re: add dropdown list server control in classs library project

MohammadAmiry29-Oct-07 19:20

MohammadAmiry

29-Oct-07 19:20

I'm not sure whether it works or not:

Try to make a custom control which wraps drop down list, and use it on your web server project.

Re: add dropdown list server control in classs library project

Ahmad Adnan29-Oct-07 21:36

Ahmad Adnan

29-Oct-07 21:36

i think u should add the refrence on ur project,then will see it

regards

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