C / C++ / MFC

Re: How do I pass String class to a function

25-Apr-08 22:56

Two different ones:

void new_function(string s)
{
// whatever
}

void new_function(string & s)
{
// whatever
}

depending on your needs.
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

Cedric Moonen25-Apr-08 23:37

Cedric Moonen

25-Apr-08 23:37

Replace the first option by:

void new_function(const string& s)
{
// whatever
}

This achieve the same result but is more efficient: you don't duplicate the object you pass to the function. The end result is the same (and even safer) because if you were trying to modify the string (in your option), this would have no impact over the original object. With passing the object as a const reference, you ensure that what is in the fact won't try to change the object.

Cédric Moonen
Software developer

Charting control [v1.4 - Updated]

Re: How do I pass String class to a function

zengkun10026-Apr-08 2:56

zengkun100

26-Apr-08 2:56

you can try str1.c_str();but this is not preferred. Big Grin | :-D

A Chinese VC++ programmer

DLL in Visual C++6

Member 430138525-Apr-08 19:31

Member 4301385

25-Apr-08 19:31

How use from Dll in VC++?
I have a Dll that into have a class and i will use from methods.
How define instances and variable?
Is solution LoadLibrary?
How in GetProcAddress Define a instance from Class?

Re: DLL in Visual C++6

Saurabh.Garg25-Apr-08 20:31

Saurabh.Garg

25-Apr-08 20:31

Do you have header and library file for the DLL. If so then include the header file and link with the library file. This[^ article have step by step instructions for how to do this.

-Saurabh

Re: DLL in Visual C++6

Hamid_RT25-Apr-08 20:40

COM unable to obtain interface -

25-Apr-08 20:40

See http://www.codeproject.com/KB/DLL/SimpleDll2.aspx[^].

act_x25-Apr-08 13:12

act_x

25-Apr-08 13:12

I have some COM client code that I am trying to write

IAdd *pAdd = NULL ;
IClassFactory *pClassFactory= NULL  ;
IUnknown *pUnknown = NULL ;

if (SUCCEEDED(CoInitializeEx(NULL, COINIT_APARTMENTTHREADED)))
{
    HRESULT res = CoCreateInstance(g_MotAutoplaycfgCLSID , NULL , CLSCTX_ALL   , IID_IUnknown , (void **)&pUnknown);
    //res = pUnknown->QueryInterface(IID_IAdd , (void **)pAdd);

     res = CoGetClassObject(g_MotAutoplaycfgCLSID , CLSCTX_ALL , NULL , IID_IClassFactory , (void **)pClassFactory );
    if(res == E_NOINTERFACE )
    {
        int x = 1;
    }
    else if(res == E_INVALIDARG)
    {
        int r = GetLastError() ;
    }
}

I can get this to retrive a valid pointer for pUnknown

HRESULT res = CoCreateInstance(g_MotAutoplaycfgCLSID , NULL , CLSCTX_ALL   , IID_IUnknown , (void **)&pUnknown);

However I am unable to obtain the interface Handle to IAdd Interface.

On the Server Side I can see that the ClassFactory class is created and that the Coclass is also instantiated.

Help is appreciated

Engineering is the effort !

Tarmo Kalda25-Apr-08 20:50

Tarmo Kalda

25-Apr-08 20:50

You can use pUnknown->QueryInterface(.. , IAdd, ....)

Tarmo.

CPallini25-Apr-08 22:50

25-Apr-08 22:50

What is the error you get?

act_x28-Apr-08 7:40

act_x

28-Apr-08 7:40

I was able to modify my client code to do this

if (SUCCEEDED(CoInitializeEx(NULL, COINIT_APARTMENTTHREADED)))
	{
		
		HRESULT  res = CoGetClassObject(g_MycfgCLSID , CLSCTX_ALL , NULL , IID_IClassFactory , (void **)&pClassFactory );

		if(SUCCEEDED(res))
		{
			// res  = pUnknown->QueryInterface(IID_IAdd,(void **)&pAdd);
			res = pClassFactory->CreateInstance(0,IID_IAdd , (void **)&pAdd);
			pClassFactory->Release(); 
		}
		else if(res == E_NOINTERFACE )
		{
			int x = 1; 
		}
		else if(res == E_INVALIDARG)
		{
			int r = GetLastError() ; 
		}
		CoUninitialize(); 
	}

The call to

HRESULT  res = CoGetClassObject(g_MycfgCLSID , CLSCTX_ALL , NULL , IID_IClassFactory , (void **)&pClassFactory );

succeeds providing a pointer to IClassFactory

However this line

res = pClassFactory->CreateInstance(0,IID_IAdd , (void **)&pAdd);

returns the following error

#define REGDB_E_IIDNOTREG                _HRESULT_TYPEDEF_(0x80040155L)

Engineering is the effort !

CPallini28-Apr-08 9:58

AddSearchProvider for all browsers

28-Apr-08 9:58

It states the class you're asking for is not registered.
Smile | :)

vikrant kpr25-Apr-08 10:50

vikrant kpr

25-Apr-08 10:50

Hey Friends

I have a search provider for which i need to create an installer

Found a way to do from webpage for internet explorer

i hope this will work for all browsers (not sure)

checked in firefox & it worked

now what i am looking at is install a search provider for all browsers using c++ or some other way in which i can create a setup & user does not have to go to the page & install the new Search Provider

and finally new Search Provider is available to all browsers.

Any idea?

http://www.microsoft.com/windows/ie/searchguide/en-uk/default.mspx?dcsref=http://runonce.msn.com/runonce2.aspx[^]
Regards

INTRODUCTION

tuneroz25-Apr-08 8:46

tuneroz

25-Apr-08 8:46

i am new and i need information on c/c++,please can any one help me on that,cause i ve really searched but no reply from friends and from webs or may be u can help me out with my research program. thanks a lot. Smile | :)

..........if there is any explaination u might want to help with,like how to start with or how to begin with{i.e INTRODUCTION ON C/C++}........i will be really grateful with ur help... Smile | :)

thanks a million.

TUNEROZ $Shucks | :-\$

tuneroz

Joan M25-Apr-08 8:51

Joan M

25-Apr-08 8:51

You can get a good reference book, they are always handy, and start trying to make a specific program you can think of it... don't try something that is too hard, start from basic things and once you find a problem ask a specific question here and a lot of great guys will come to your help...

Be sure to post a clear and well formed question and it will be better...

Here you have plenty of articles speaking about different topics, they are separated in levels so you can find some that are for novice people.

You are welcome to this family/community... Roll eyes | :rolleyes:

Good luck! Rose | [Rose]

Hamid_RT25-Apr-08 9:15

25-Apr-08 9:15

tuneroz wrote:
i ve really searched but no reply from friends and from webs

You can ask your questions here and usually you can get your asnwers. Wink | ;)

See www.Cplusplus.com[^].

tuneroz25-Apr-08 9:26

tuneroz

25-Apr-08 9:26

thanks 4 the help my big bro.am really grateful......... Rose | [Rose]

tuneroz $Shucks | :-\$

tuneroz

Hamid_RT25-Apr-08 20:41

25-Apr-08 20:41

You're welcome,I think its good point for start. Wink | ;)

CPallini25-Apr-08 9:56

25-Apr-08 9:56

Google is your friend [^].
Smile | :)

Hamid_RT25-Apr-08 20:38

25-Apr-08 20:38

CPallini wrote:
Google is your friend

Im not sure! Wink | ;)

CPallini25-Apr-08 22:47

25-Apr-08 22:47

You're probably right. Anyway, perhaps Google will be his new friend.
Big Grin | :-D

Hamid_RT26-Apr-08 4:18

Required C++ source code for below question

26-Apr-08 4:18

CPallini wrote:
You're probably right. Anyway, perhaps Google will be his new friend.

ChayaMandini25-Apr-08 6:49

ChayaMandini

25-Apr-08 6:49

Hi, I have below a question on programming in C++ which seems complicated to me.Please help asap.

A shop wishes to have a computerised system for its cashier. The program should help the
cashier to calculate the total payment required to be performed by each customer. It also should
be able to keep record of the number of customers for a day, calculate the total income of the
shop for the day as well as the average amount spent by a customer. You can assume that for
each customer coming to the counter, the cashier can find out how many different items he/she
has purchased before inputting the details of the purchase. However, the cashier does not
know, in the morning, the number of customers that are likely to visit the shop for the day.
Write a program that can perform the required work for the cashier. Your program should have
the following features:
• It allows the input of a number n, representing the number of items to be purchased by the
customer.
• It then allows the input of n pairs of values representing the quantity and price per unit for
each of the n items. For each item, the computer needs to display the total resulting amount.
• It Calculates and displays the total payment to be performed by the customer.
After having displayed the required values for a customer the program should ask the user
whether to input for a new customer. If the answer is yes, the program should repeat the
above steps. Otherwise, it should display the following values
• The number of customers.
• The total amount paid by all customers
• The average amount spent by a customer.
Your program should perform the following validations:
• Quantity of an items should be in the range 1..10.
• Price of an item should be greater than 0 and not more than 100.00.
For input, the computer should give the user the item number and the user should enter the
values of quantity and price. The computer should immediately display the total amount to be
paid for that item. A typical user screen, for one customer, should look as
below:
Item Quantity Price Per Unit Total Cost
1 2 20.00 40.00
2 3 25.50 76.50
3 1 30.00 30.00
Total 146.50
You may use an array to store the data pertaining to the different customers.

Re: Required C++ source code for below question

CPallini25-Apr-08 6:58

Re: Required C++ source code for below question

25-Apr-08 6:58

Please make yourself your homework.
Smile | :)

Maximilien25-Apr-08 7:08

Maximilien

25-Apr-08 7:08

I'm certain BOOST already have a template for that.

boost::homework< cash_system >

Maximilien Lincourt
Your Head A Splode - Strong Bad

Re: Required C++ source code for below question

Hamid_RT25-Apr-08 7:11