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In C++, there is no overloading across scopes ,
Please see following example
#include<iostream>
using namespace std;
class B {
public:
int f(int i) { cout << "f(int): "; return i+1; }
// ...
};
class D : public B {
public:
double f(double d) { cout << "f(double): "; return d+1.3; }
// ...
};
int main()
{
D* pd = new D;
cout << pd->f(2) << '\n';
cout << pd->f(2.3) << '\n';
}
which will produce:
f(double): 3.3
f(double): 3.6
rather than the
f(int): 3
f(double): 3.6
Why it is so?
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to gain required result simply declare functions with the different argument types in one class...
perhaps u mixed up overloading with overriding
class D : public B {
public:
double f(double d) {
cout << "f(double): ";
return d+1.3;
}
int f(int i) {
cout << "f(int): ";
return i+1;
}
// ...
};
4apai
There're no impossible tasks. There're tasks that required infinite period of execution time.
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No that is not What I Expect...Please read the question carefully.
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C++ allows specification of more than one function of the same name in the same scope. These are called “overloaded functions”. 
Cheers,
Vishal
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You may expect the f(int) method to be called, but in resolving the call I suspect the compiler 'sees' that by casting the int to a double, it can resolve to a method within the class. Have you tried either of these?
cout << pd->f((int)2) << '\n';
cout <<((B*)(pd))->f(2) << '\n';
Chris Meech
I am Canadian. [heard in a local bar]
Gently arching his fishing rod back he moves the tip forward in a gentle arch releasing the line.... kersplunk [Doug Goulden]
Nice sig! [Tim Deveaux on Matt Newman's sig with a quote from me]
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Hi All,
My question is not how to overcome the above problem. I need to know why C++ dosen't allow the overloading across the scopes?
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vikrams wrote:
overloading across the scopes?
I need to understand what you mean by the above. 
Chris Meech
I am Canadian. [heard in a local bar]
Gently arching his fishing rod back he moves the tip forward in a gentle arch releasing the line.... kersplunk [Doug Goulden]
Nice sig! [Tim Deveaux on Matt Newman's sig with a quote from me]
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Hi,
I have a project with only limited harddisk space. I have bought VS.net 2003 package, but I only want to install VC++ (without .net framework, i.e. I don't want to use VC++.net), how to do this? Thanks!
Thomas
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how to using shockwave flash component in vc++
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if u have installed flash in your machine u can use the ActiveX control....
i have tried it in VB...:->
just insert that activex control in ur VC formview...
all the best..
- thanks and regards,
Basavaraj P.Umadi
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i want use Windows media sdk....but any problem,,,, i want to use get_duration function..
i need information about current play time and total time and bitrate ,,,
but i dont know use get_duration function .....how i can use that? for example explain...
i m this sdk beginning,,,,, i want that use CWindowMedia:: <this> ,,,,,
<this>... is get_duration must in.....
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I am creating a bunch of dockable dialog bars that have several Edit controls in them to display data. I am doing this within a SDI application. Basicaly I am trying to create lots of little "tool bars" that I can organise on the screen as I want and hide/show at will. Think the tool bars in an application like flashMX or photoshop and thats what Im aiming for, just less complicated using standard controls arranged in the dialog editor.
Given that the SDI wizard (in vis6C++) doesnt create a data map so I can assign a variable and use UpdateData to display variables in these edit boxes that are within the dialog bars, how do I go about setting the data in them. I know I can use SetText and GetText but theyre only good for text, I want to display DOUBLEs and other numerical data in them.
I guess what I am asking is, what is the standard way to control the content of Edit controls that are found in DialogBars?
Alternatively if someone else has a better idea as to how to create an extensible interface that is based on controls I would love to hear it. If you know how to make a modeless dialog box dockable, I could use them for "Pseudo dialog bars" and that would also solve my problems as they have message and data maps setup by the IDE.
Thanks again,
Will.
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Imho, the "right" approach to this problem is to dissociate the GUI from the data.
I recommend sending a custom message to each of the dialog bars which causes them to query a central source of data (a pointer to which can be obtained via a public method of your app) and update themselves as needed. This allows the nature of the displayed information to be known only to the dialog bar(s) that display the information.
Your dialog bar(s) would do something like this:
CFooDialogBar::OnUpdateMyself()
{
CMyData* pData = ((CMyApp *) AfxGetApp())->getData();
float fValue_1 = pData->getValue_1();
int nValue_2 = pData->getValue_2();
...
}
/ravi
My new year's resolution: 2048 x 1536
Home | Articles | Freeware | Music
ravib@ravib.com
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But the thing is that Dialogbars dont handle their own messages. Events are passed to the parent window, there is no class for them, theyre built on top of the main frame class i.e.
Class CMainFrame : public CFrameWnd
which receives all the events for every dialogbar.
The issue Im having is that I dont know how to address the edit boxes. Im a novice MFC programmer and all Ive ever used to populate the boxes is UpdateData.
Does someone have a code snippet that shows me how to populate the box with something (other than an int or string i.e a float)?
Thanks,
Will.
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Who has some clues on creating WinLogon Notification Package using VS.NET 2003. Be more specific,
- what project type should I create.
- any special settings?
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Just Create a Simple Win32 based DLL. no extra setting needed.
Be sure that you export all the function that required by winlogon.exe i.e. which you going to mention in REGISTRY
"I Think this Will Help"
[Vote One Here,.....]
<h5
alok gupta="" <br=""> visit me at http://www.thisisalok.tk
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Does anyone know how to add a string to the resource string table at runtime? I have a control that takes a string resource to initialize, but I want to init things dynamically. Any ideas?
~Nitron.
ññòòïðïðB A
start
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Nitron wrote:
Any ideas?
How about using UpdateResource(..., RT_STRING, ...)?
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
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The string table is just another resource, you can change it with the *UpdateResource() functions (but only on NT). I have some code for modifying the table, but it's for work so I can't share it.  However check out The format of string resources[^] in RaymondC's blog, which should be a good starting point for you.
--Mike--
LINKS~! Ericahist updated! | 1ClickPicGrabber | CP SearchBar v2.0.2 | C++ Forum FAQ
Strange things are afoot at the U+004B U+20DD
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I still wonder if he can perform this at runtime.
Won't his DLL or EXE file be locked down from writing?
An alternative would be to hook the LoadString API and watch for a 'magic' resource number and supply his own string out of an internal table of text srings. I would bet the call to get the string out of the string table the 'control' is using devolves into a call to LoadString.
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oh... yeah, I didn't think the question was about changing his own program's string table. I don't know if that will be possible, best thing to do is try it and see what happens.
--Mike--
LINKS~! Ericahist updated! | 1ClickPicGrabber | CP SearchBar v2.0.2 | C++ Forum FAQ
Strange things are afoot at the U+004B U+20DD
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Hello. Thiss is my first post. :->
The problem...
I'm programing a service that connect to one DB in Oracle,
using threads to with request.For wainting for a new request
i use
while (_this->running) {
db_connection = new DBConnection(param1,param2,param3);
then i connect...
try {
db_connection->DBConnect();
TRACE("Connected to DB.\n");
} catch(int) {
(ERROR)
}
Everything ok...
then read data...
try {
db_connection->StartFeeds();
TRACE("StartFeeds OK.\n"); ( NEVER Happens 
} catch(int) {
TRACE("StartFeeds Not OK.\n");
delete db_connection;
Sleep(2000);
continue;
}
}
The problem, i use TOAD to see the program run... and i see inactive programs grow and grow...
Can you help me?
Another question,
In Startfeeds i use
static text sqlstmt[] = "BEGIN :status := pck_oracle.start_feeds; END;";
but pck_oracle have
I_QUEUE_NAME VARCHAR2 (input)
,O_SUCESS OUT NUMBER (output)
,O_SUCESS_MSG OUT VARCHAR2 (output)
how do i pass the input field and recive the two output fields?
Can you explain me this?
Thanks a lot for your pacience 
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Hi everyone!
I need to learn programming the parallel (and serial) port in C++ for Windows 2000, XP ...
I kwow that this is done by opening the port with CreateFile("LPT1"... and then I can send and receive data with WriteFile and ReadFile. 
My problem is that my WriteFile doesn't return and it waits something.
So my questions are:
Do I need to use a driver or something like that?? If so, I don't want to Download any Driver, I would like to do everything by myself :-> (System-Supplied Drivers)
Do I need to send any control settings to the port?? If so, how on earth do I do that!!!
Finally! Do I need to physically send any control signals to the port 
BIG Please, help me!
Thanks 
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2000 and XP do not allow you to write directly to memory 0x378-0x37f (parallel port). So you do need a driver to do this for you. There are free programs out there. Try UserPort. It somewhat works for me. The driver doesn't always stay installed and you have to run this small program to reinstall it sometimes.
DirectIO is another one. Costs 30$.
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