C / C++ / MFC Discussion Boards

Re: How can extract a Return Value from a Stored Procedure with ADO

Jon Hulatt14-May-02 23:54

Jon Hulatt

14-May-02 23:54

I can't be arsed to read your code. But heres a snippet from some of my code that does what you want:

try {
		_CommandPtr pCommand;
		_ParameterPtr pRetVal;

		pCommand.CreateInstance(__uuidof(Command));
		pCommand->ActiveConnection = m_pConn;
		pCommand->CommandText = "p_YourProc";
		pCommand->CommandType = adCmdStoredProc;
	
		// Create and add return value param
		pRetVal = pCommand->CreateParameter ( _bstr_t ("RETURN_VALUE"), adInteger, adParamReturnValue, 0);
		pCommand->Parameters->Append(pRetVal);

		// create and add taskid param
		pCommand->Parameters->Append ( pCommand->CreateParameter( _bstr_t ("YourParamIn"),adInteger,adParamInput,0 ,_variant_t(lTicketId)));
		pCommand->Execute(NULL, NULL, adCmdStoredProc);

                // this is the bit you're interested in
		lSuccess = (DWORD) pRetVal->GetValue();
	} catch (_com_error e)
	{
		//handle error
	}

Signature space for rent. Apply Within.

Re: How can extract a Return Value from a Stored Procedure with ADO

youssef15-May-02 2:52

youssef

15-May-02 2:52

Hi, thank for the answer but I can't receive the return value.

lSuccess is allways null.

best Regards

youssef

Re: How can extract a Return Value from a Stored Procedure with ADO

Jon Hulatt15-May-02 3:08

Jon Hulatt

15-May-02 3:08

paste the source of your stored procedure.

STL is a religeon. Enquiries to Reverend Christian Grauss

Re: How can extract a Return Value from a Stored Procedure with ADO

Carlos Antollini15-May-02 3:27

Carlos Antollini

15-May-02 3:27

Use My class CADODatabase, You have the CADOCommand and CADOParameter Class...

For other side, if you want to return a value by the parameter, you mus tu use the following sintax in the stored prodedure

Create Procedure MyProc 
@Param1 Integer,
@ParamRet varchar(100) output
AS
...
Select @ParamRect = "Hello World"
Go

Regards

Carlos Antollini.
www.wanakostudios.com
Sonork ID 100.10529 cantollini

Re: How can extract a Return Value from a Stored Procedure with ADO

Jon Hulatt15-May-02 5:14

Jon Hulatt

15-May-02 5:14

Carlos Antollini wrote:
Select @ParamRect = "Hello World"

should be :

Select @ParamRect = 'Hello World'

SQL server is picky about that.

But he wanted a procedure's return value, not to return a value. Theres a difference(!)

STL is a religeon. Enquiries to Reverend Christian Grauss

Re: How can extract a Return Value from a Stored Procedure with ADO

Carlos Antollini15-May-02 5:27

Carlos Antollini

15-May-02 5:27

If he wants to get the value returned by the stored procedure must to use the adParamReturnValue value..... Wink | ;)

Check here

Best Regards

Carlos Antollini.
www.wanakostudios.com
Sonork ID 100.10529 cantollini

Re: How can extract a Return Value from a Stored Procedure with ADO

Jon Hulatt15-May-02 5:38

Jon Hulatt

15-May-02 5:38

My original reply shows him how to do just that!!!

STL is a religeon. Enquiries to Reverend Christian Grauss

Re: How can extract a Return Value from a Stored Procedure with ADO

Carlos Antollini15-May-02 5:48

Carlos Antollini

15-May-02 5:48

It's True, You have the reason

Sorry Blush | :O

Carlos Antollini.
www.wanakostudios.com
Sonork ID 100.10529 cantollini

Re: How can extract a Return Value from a Stored Procedure with ADO

Jon Hulatt15-May-02 5:46

Jon Hulatt

15-May-02 5:46

STL is a religeon. Enquiries to Reverend Christian Grauss

Threads and server side applications

unknown soldier14-May-02 23:44

unknown soldier

14-May-02 23:44

Hi!!!

Can anyone tell me the meaning of phrase "thread pool".

Actually i read certain articles on Server based applications at CP. Many people suggest that allocating one thread per user is a bad approach. People suggest that there are two other options one is I/O completion ports and the other is "thread pool"

Here i am unable to understand the meaning of "thread pool". As far as my vocabulary is concerned, the meaning of word pool is "standing water".

Please tell me the meaning of "thread pool"

Re: Threads and server side applications

Nish Nishant14-May-02 23:55

Nish Nishant

14-May-02 23:55

You have a fixed number of threads. If the number of connections is less than the number of threads, you can give one thread per user. If the user count is higher the users are divided across the threads. This collection of threads is the thread pool. Like if the thread pool has 10 threads and you have to server 30 clients, each thread will handle 3 clients. This is a very simplistic explanation and the actual technical details, might be rather more complicated.

Nish

Regards,
Nish
Native CPian.
Born and brought up on CP.
With the CP blood in him.

Re: Threads and server side applications

unknown soldier15-May-02 0:01

unknown soldier

15-May-02 0:01

Oh thanks Mr.Nish for the reply, now i understand what is thread pool.

Also thanks for your "simple" artiles on Client-Server I/O. Really as a beginner I learn't a lot from them. I don't know why the rating is so low????

Multi-language

14-May-02 23:43

Nowadys, I often find that many softs use ini files, instead of dll files, to support multi-languages such as Flashget, Netants, Createinstall and so on. They employ a ini file to support another language, and need not modify the exe file. As a result, this method is better than the former. But I can not think of how to do it. Can you give me a favour?
Thank you. Smile | :)

Re: Multi-language

Christian Graus15-May-02 3:03

Christian Graus

15-May-02 3:03

I forget the names, but Microsoft provides heaps of API calls for ini files. Nevertheless, C++ iostreams are more than up to the task if you don't mind doing a little parsing.

Christian

The tragedy of cyberspace - that so much can travel so far, and yet mean so little.

And you don't spend much time with the opposite sex working day and night, unless the pizza delivery person happens to be young, cute, single and female. I can assure you, I've consumed more than a programmer's allotment of pizza, and these conditions have never aligned. - Christopher Duncan - 18/04/2002

Re: Multi-language

Paul M Watt15-May-02 8:27

Paul M Watt

15-May-02 8:27

If you are asking what the INI functions are, here you go:

GetPrivateProfileString
GetPrivateProfileInt
GetPrivateProfileSection
GetPrivateProfileSections
GetPrivateProfileStruct

as well as the WritePrivateProfileXXX versions of all of these functions.

I would not reccomend trying to parse these files yourself as the API functions provide quite a bit of error checking and handling for you.

If you are wondering how to use this data in your program, I would create a set of global variables that have IDS associated with them, and the IDS will have the corresponding string in the ini file.

I would recommend that you look into string tables and create a resource only DLL in order to hold these Multi-language strings. You can create a string table with multiple LCID or locale IDS, that are associated with different langauges. Then you would create all of the string entries in this table, and you would only be responsible for selecting the correct LCID. When you load the string from the table it will get the correct one for you.

This also solves the problem from managing the different number of ini files, and prevents users from messing around and being able to edit these files.

Good Luck!

Build a man a fire, and he will be warm for a day
Light a man on fire, and he will be warm for the rest of his life!

Re: Multi-language

15-May-02 22:57

Thank you very much. I had known how to support multi-languages with dlls. But nowadays, I see many softs use ini files instead of dlls, so i think it must has some good things, or they will not do this. I also find that they also use the code_page. How to modify the code_page dynamicly?
thank you very much.
Smile | :)

Help................................

johny quest14-May-02 23:26

johny quest

14-May-02 23:26

Hello all

I am developing an application which contains three panes.In the left most and middle pane, trees are displayed.I want to give user following facilities,plz help me in this regard.
1: To drag and drop nodes from the middle pane to the left most pane.Can anybody tell me how to do it?

2:I want to save the whole tree in both panes on hardisk and later load it back so that user can edit,delete and make new nodes in existing tree.Please suggest what will be the best method

3:I want to give my application an auto saving option like in MS Word which activates(saves) after a specified interval of time.

regards

Re: Help................................

Jon Hulatt15-May-02 0:12

Jon Hulatt

15-May-02 0:12

1. I'm assuming your "panes" contain CTreeCtrl or CTreeViews. You can look at the documentation in MSDN for dragging and dropping from CTreeCtrl. The documentation really is quite good.

2. oh dear.

3. once you've implemented (2), create a timer, and in the timerproc call the function from (2).

STL is a religeon. Enquiries to Reverend Christian Grauss

ReadFile function

14-May-02 22:54

Hi there!
I'd like to use the ReadFile function to read data from a serial port. But there are few thing that I don't really understand.
So here's this function:
ReadFile(HANDLE hFile, // handle of file to read
LPVOID lpBuffer, // address of buffer that receives data
DWORD nNumberOfBytesToRead, // number of bytes to read
LPDWORD lpNumberOfBytesRead,// address of number of bytes read
LPOVERLAPPED lpOverlapped // address of structure for data
);

What i don't relly understand is:
nNumberOfBytesToRead - I know that it shows, how many bytes i want to read, but is it changed when the function returns? I saw that some people uses it to see how many bytes were recieved. Does it show it? Or maybe the lpNumberOfBytesRead does show it.

Thanks for the answers!

Re: ReadFile function

Niklas L14-May-02 23:24

Niklas L

14-May-02 23:24

Rudy Brown wrote:
Or maybe the lpNumberOfBytesRead does show it.

Yes.

nNumberOfBytesToRead is just the size of your buffer (lpBuffer). I.e the maximum number of bytes you can receive in one call.

MultiThreaded Progress bar

SamirSood14-May-02 22:36

SamirSood

14-May-02 22:36

I have a program in which i have a background process running and i have to update the progress of the Progress bar according to the activities of the Background process .
Can Anyone suggest a solution.

Samir Sood

Re: MultiThreaded Progress bar

Jon Hulatt14-May-02 23:57

Jon Hulatt

14-May-02 23:57

put your "background process" in a worker thread. Then your main (UI) thread is free to redraw the screen.

Signature space for rent. Apply Within.

Re: MultiThreaded Progress bar

SamirSood15-May-02 0:14

SamirSood

15-May-02 0:14

Could u please post a code snippet of that.

Samir Sood

Re: MultiThreaded Progress bar

Todd Smith15-May-02 7:31

Todd Smith

15-May-02 7:31

Or put your progress dialog in its own thread. Either way will work.

Todd Smith

code for MultiThreaded Progress bar

Hesham Amin15-May-02 0:45

Hesham Amin

15-May-02 0:45

Hi..
I know two ways to do so:
The first:
to pass a handle of a progress bar to the worker thread and use it as follows

1. Create a helper class that will hold data passed to the worker thread:

<br />
class CData<br />
{<br />
HWND m_hWnd;<br />
//Athor class members..<br />
}<br />

2. In the dialog class create a member variable of type CData:
private:
CData MyData;

3. Before the call to AfxBeginThread() fill members of CData :

<br />
{<br />
//..<br />
//.. some of your code<br />
MyData.m_hWnd=(GetDlgItem(IDC_PROGRESS))->m_hWnd; //where IDC_PROGRESS <br />
<br />
is the ID of the progress bar..<br />
<br />
//now call AfxBeginThread<br />
AfxBeginThread(WorkerFn,&MyData, /*Ather args..*/);<br />
}<br />

4. In the Worker thread function write the following code:

<br />
UINT WorkerFn(LPVOID pData)<br />
{<br />
CData* data=(CData*)pData;<br />
CProgressCtrl* progBar=CWnd::FromHandle(data->m_hWnd);<br />
<br />
//Now use progBar as you wish!<br />
progBar->SetRange(0,100);<br />
//etc<br />
<br />
}<br />

The second:
Pass the handle of the dialog enstead of the progress bar then use:

<br />
::PostMessage(data->m_hWnd,WM_USER+1,0,0)<br />

and handle the message in the dialog..

Send again if you find any problems..

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.