Re: converting WCHAR[] to BYTE[] - C / C++ / MFC Discussion Boards

lsh486love11-Aug-09 19:26

11-Aug-09 19:26

I want to use a dll in Visual C++ (Active X control), and for that i did the following:
ClassWizard->Add class->From a type library

Now i have the files that I need (.cpp and .h), but when I invoke a method, I get this message in my output:

"Warning: attempt to call Invoke with NULL m_lpDispatch!"

And the method does nothing. I think I have to create a LPDISPATCH object, but i don't know how. Any help???

My dll file name is "HanBarcord.dll".
and class name in the dll file is "Cbarcord".

I think I have to create the pointer to the real COM's IDispatch.
So, I'm trying to use the object's CreateDispatch function member.
But I don't know what I should put into parameter of "barcordreader.CreateDispatch" exactly.

COleException *e = new COleException;
Cbarcord barcordreader;
barcordreader.CreateDispatch(" ????????????? ", e);

Thank you in advance .

Re: the way to use a DLL in Visual C++.

CPallini11-Aug-09 20:59

CPallini

11-Aug-09 20:59

You should pass the CLSID or the ProgID of the automation object, see [^].

You may also get better help posting at the COM forum [^].
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

[My articles]

Re: the way to use a DLL in Visual C++.

Stuart Dootson11-Aug-09 21:40

Stuart Dootson

11-Aug-09 21:40

The CLSID, which should be recorded in the typelib somewhere.

I prefer using #import, which exposes the whole of a type-lib, including the CLSIDs.

Here's an example - I'm using Excel's _Application class (it's a COM class - you could use it via MFC's 'Add Class' route:

// Do the import - need to rename some things to avoid name collisions
#import "libid:00020813-0000-0000-C000-000000000046" version("1.6") auto_search no_dual_interfaces rename("DialogBox", "excelDialogBox") rename("RGB", "excelRGB") rename("DocumentProperties", "excelDocumentProperties") rename("SearchPath", "excelSearchPath") rename("CopyFile", "excelCopyFile") rename("ReplaceText", "excelReplaceText")

int main(int, char**)
{
   CoInitializeEx(0, COINIT_APARTMENTTHREADED);
   {
      // Create the Excel object (or get the active instance) - note
      // that the CLSID of the Excel application class is linked to
      // the structure (Excel::Application) generated for that class
      // and can be accessed using __uuidof.
      Excel::_ApplicationPtr xl;
      if (SUCCEEDED(xl.GetActiveObject(__uuidof(Excel::Application))))
      {
         std::cout << "Getting name\n";
         // We're using several auto-generated classes here (Excel
         // application, Excel workbook) - you'd have to import each
         // one separately with MFC!
         std::cout << xl->ActiveWorkbook->FullName << std::endl;
     }
   }
   CoUninitialize();
}

If you're using VC6 (which I'm guessing you are?), I'm not sure how well #import will work for you, though Frown | :-(

Java, Basic, who cares - it's all a bunch of tree-hugging hippy cr*p

converting WCHAR[] to BYTE[]

RajeshRPR11-Aug-09 18:56

RajeshRPR

11-Aug-09 18:56

Hi,

I am trying to convert wchar[] content to byte[]... but to my surprise, all the suggested methods went in vain..
i used widechartomultibyte,wcstomobs .... they all reproduced "???" marks instead of characters, when i use Chinese or japanese content..

can anyone help me how to convert content without any loss??

Aim: my objective is to read byte by byte of wchar[] content and convert it to byte[]..

i'd be graterful to your reply.

Thanks,
Rajesh.

Re: converting WCHAR[] to BYTE[]

Sarath C11-Aug-09 20:24

Sarath C

11-Aug-09 20:24

You can allocate byte array and copy the data using memcpy. if you're using chinese or japanese characters it's hard to keep in single byte format. wchar_t is two byte so you may need to allocate 2* actual wchar elements to contain everything in the byte array. What is the purpose after converting to a byte array?

-Sarath.

My blog - Sharing My Thoughts

Rate the answers and close your posts if it's answered

Re: converting WCHAR[] to BYTE[]

Cedric Moonen11-Aug-09 20:34

Cedric Moonen

11-Aug-09 20:34

I suppose you are the same guy as Rakesh5 that posted this question yesterday ? (Why do you create multiple accounts ?)

RajeshRPR wrote:
they all reproduced "???" marks instead of characters,

David asked you yesterday where these characters are displayed. Are you inspecting the byte array with your debugger ? If yes, then it is normal that the characters are not displayed properly, because the debugger inspects an array of unsigned chars and not a string.

Cédric Moonen
Software developer

Charting control [v2.0]
OpenGL game tutorial in C++

Re: converting WCHAR[] to BYTE[]

RajeshRPR11-Aug-09 21:14

RajeshRPR

11-Aug-09 21:14

Hey Cedric,

I am his friend..We are working together.. i dont know he posted anything like that.. Hence, i posted today.

Have you replied him anything?

Thanks,
Rajesh

Re: converting WCHAR[] to BYTE[]

Bacon Ultimate Cheeseburger11-Aug-09 20:43

Bacon Ultimate Cheeseburger

11-Aug-09 20:43

RajeshRPR wrote:
can anyone help me how to convert content without any loss??

There is no conversion between Chinese or Japanese and the ANSI code page. If you need to retain the contents and use it as a multibyte string you will need to convert it to UTF8. You can do this by using CP_UTF8 instead of CP_ACP when calling WideCharToMultiByte().

1300 calories of pure beef goodness can't be wrong!

Static Compilation in .net project/ Dependancy of EXE file over Visual Studio Installation

Madhu_Rani11-Aug-09 18:44

Madhu_Rani

11-Aug-09 18:44

I developed an application by using Visual Studio 2005 (Visual C++/MFC based project). The developed exe works fine over the machine that already have installation of Visual Studio 2005. But it does not run over other machine. I even installed the .net2 frameowrk and service pack of .net2 framework as well but did not succdeed in running the application.

I remember that in old days, there was an option of static compilation in Visual C++ (6 version) without .net framework. So how we can do the same in Visual Studio 2005 that is dependant over .net framework. In static compilation, the compiler/linker put all the dependant stuff in exe file.

Please guide me how I can run the application over machines that does not have installation of Visual Studio 2005.

THANKS.

Re: Static Compilation in .net project/ Dependancy of EXE file over Visual Studio Installation

Randor 11-Aug-09 21:46

Randor

11-Aug-09 21:46

Madhu_Rani wrote:
Please guide me how I can run the application over machines that does not have installation of Visual Studio 2005.

Dynamic linked Visual Studio 2005 C++ applications may require the C run-time and MFC libraries installed on the client machine.

Microsoft Visual C++ 2005 Redistributable Package (x86)[^]
Microsoft Visual C++ 2005 SP1 Redistributable Package (x86)[^]

Another option is to static link your project by choosing 'Use MFC in a Static Library' in the General section of your configuration properties. You will also need to choose '/MT' runtime library in the Code Generation section.

Best Wishes,
-David Delaune

Titlebar

kumar sanghvi11-Aug-09 18:32

kumar sanghvi

11-Aug-09 18:32

Hi,
Is it possible to change the height of titlebar of all Dialogs which are used only in my application using WM_NCCALCSIZE or DrawCaption() ..if yes please suggest me any sample which does the same....

Re: Titlebar

Sarath C11-Aug-09 20:27

Sarath C

11-Aug-09 20:27

Check these

http://www.catch22.net/tuts/custom-titlebar
[^]

A Technique to Customize the Title Bar of Windows[^]

-Sarath.

My blog - Sharing My Thoughts

Rate the answers and close your posts if it's answered

c implementation vs java implementation of bzip2

raytsu11-Aug-09 17:01

raytsu

11-Aug-09 17:01

hello to all

i don't know if this is the right place to post this.. Smile | :)

but im posting it anyway.. Smile | :)

i am having a problem extracting a zipped(bzip2 format) file which is produced by a java implementation of bzip2 program.
the extraction is using c implementation.

is there any difference between c implementation(libbzip2) and java implementation(BZip2OutputStream
) of bzip2?

please help... Frown | :(

(^_^)

Determining if CListCtrl is in EditMode

Mike Hankey11-Aug-09 11:08

Mike Hankey

11-Aug-09 11:08

Using C++ 6.0

I have a list control CListCtrl and am doing inplace edit and is working fine but I need to trap keyboard input using PreTranslateMessage and in this method I need to determine if the List item is currently being edited.

Any help appreciated,
Mike

"It doesn't matter how big a ranch ya' own, or how many cows ya' brand, the size of your funeral is still gonna depend on the weather." -Harry Truman.

Semper Fi
http://www.hq4thmarinescomm.com[^]
My Site

Re: Determining if CListCtrl is in EditMode

Michael Dunn11-Aug-09 11:41

Michael Dunn

11-Aug-09 11:41

You can listen for the LVN_BEGINLABELEDIT/LVN_ENDLABELEDIT pair, or use LVM_GETEDITCONTROL.

--Mike--
Dunder-Mifflin, this is Pam.

Re: Determining if CListCtrl is in EditMode

Mike Hankey11-Aug-09 14:29

Mike Hankey

11-Aug-09 14:29

Duh, why didn't I think of that?

Good Eye, thanks
Mike

"It doesn't matter how big a ranch ya' own, or how many cows ya' brand, the size of your funeral is still gonna depend on the weather." -Harry Truman.

Semper Fi
http://www.hq4thmarinescomm.com[^]
My Site

iContextMenu on x64, inside CFileDialog

C^hris L^osinger11-Aug-09 8:57

C^hris L^osinger

11-Aug-09 8:57

i have an Explorer context menu extension. it works in Vista and XP, Win32 and x64 without problem - as long as you're right-clicking from within Explorer. it uses IContextMenu3 and IShellExtInit.

in Win32, you can also right-click and use the extension from within any common file open dialog (ex. CFileDialog - yes, using the new-style dialogs). but in Vista 64 and XP 64, my extension doesn't show up in the file open dialog. again, it all works fine from plain old Explorer (desktop, My Computer, an official Explorer window, etc.).

so, it looks like the common file dialog's context menu is doing something slightly different in x64. but i can't find any reference to any such changes...

anyone else run into this ?

image processing toolkits | batch image processing

Re: iContextMenu on x64, inside CFileDialog

Randor 11-Aug-09 11:05

Randor

11-Aug-09 11:05

Chris Losinger wrote:
anyone else run into this ?

Hi Chris,

I have recently started using Windows7 x64 as my development box and I am also experiencing problems with Explorer context menu extensions that worked fine on 32 bit XP. My extensions simply do not appear... I have not spent any time researching the cause of the issue. If you figure it out before I do post your results here. I'll do the same.

Best Wishes,
-David Delaune

Re: iContextMenu on x64, inside CFileDialog

C^hris L^osinger11-Aug-09 11:21

C^hris L^osinger

11-Aug-09 11:21

if they don't appear at all, you probably need to tweak your defn of GetCommandString. it changed in x64.

#ifdef _WIN64
   STDMETHOD(GetCommandString)(UINT_PTR, UINT, UINT*, LPSTR, UINT);
#else
   STDMETHOD(GetCommandString)(UINT, UINT, UINT*, LPSTR, UINT);
#endif

but that won't fix the file dialog issue i'm having.

image processing toolkits | batch image processing

Re: iContextMenu on x64, inside CFileDialog

harold aptroot11-Aug-09 11:21

harold aptroot

11-Aug-09 11:21

I've been using XP x64 for a while and I noticed some odd context menu behaviour from some programs - like only appearing in the 32bit Explorer, but I never really looked into it, and this seems to be something different anyway, so I have no real answer for you (sorry!)

compile error on this open printer statement

Robert V. Klein11-Aug-09 8:06

Robert V. Klein

11-Aug-09 8:06

HDC hdcPrinter;

OpenPrinter(pn, &hdcPrinter, NULL);

I get a compile error on arg 2 &hdcprinter which says invalid conversion from HDC to Void I am using the compiler Dev-C++

What is wrong. All examples have seen show that this should work,

Re: compile error on this open printer statement

Cedric Moonen11-Aug-09 8:19

Cedric Moonen

11-Aug-09 8:19

Could you please provide:
- The exact error message (copy/paste)
- The type of hdcPrinter

Cédric Moonen
Software developer

Charting control [v2.0]
OpenGL game tutorial in C++

Re: compile error on this open printer statement

Robert V. Klein11-Aug-09 8:35

Robert V. Klein

11-Aug-09 8:35

the printer is HP Photosmart C7100 series which is pointed to by pn

hdcPrinter is declared as HDC hdcprinter.

Copy & paste doesn't work in the compiler window I will try and type it.

In function 'BOOL SavePrintFile(HWND_*,HDC_)'.
invalid conversion from 'HDC_ **'to 'void**'
initilizing argument2 of 'BOOL OpenPrinterA(CHAR*,void**,_PRINTER_DEFAULTSA)'
[Build Error] [maingfa.o] Error 1

Re: compile error on this open printer statement [modified]

Randor 11-Aug-09 10:32

Randor

11-Aug-09 10:32

The OpenPrinter Function[^] expects the second argument to be a HANDLE not an HDC.

Here is an example of using OpenPrinter to open the default printer using the GetDefaultPrinter Function[^]

#include <Winspool.h>
HANDLE OpenDefaultPrinter(ACCESS_MASK dwMask)
{
	HANDLE hPrinter = INVALID_HANDLE_VALUE;
	PRINTER_DEFAULTS pDef = {0};
	DWORD dwSize;

	GetDefaultPrinter(NULL, &dwSize);
	TCHAR* szBuffer = (TCHAR *)alloca(sizeof(TCHAR) * dwSize);

	if(NULL != szBuffer)
	{
		if(GetDefaultPrinter(szBuffer, &dwSize))
		{
			pDef.DesiredAccess = dwMask;
			OpenPrinter(szBuffer, &hPrinter, &pDef);
		}
	}
	return hPrinter;
}

//Usage:
OpenDefaultPrinter(PRINTER_ALL_ACCESS);

Best Wishes,
-David Delaune

[UPDATE]
You should remove my call to alloca and use heap-based memory allocation with the new/delete operators. My personal projects usually have structured exception handler for stack overflows and I inadvertently used alloca in this comment.

modified on Tuesday, August 11, 2009 4:46 PM

Read 1000 Lines from text file in a single shot ........

spalanivel11-Aug-09 6:51

spalanivel

11-Aug-09 6:51

Hi,
Below is the line of code(C++) for Reading the Textfile line by line.
CString = strFilePath; // text path file path
ifstream Textfile;
Textfile.open(strFilePath,ios::in);
std::string value;
while(!Textfile.eof())
{
getline(Textfile,value); // Read line by line...

}

Textfile.close();

Now the question is I am having 40MB text file size. I need to read 1000 Lines in a single shot (And upto read 1000 times to reach the whole 40 MB size) not line by line. How to do this?
(ie from 1 to 1000 and 1001 to 2000.... reach max lines)
reg,
Subbu

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