Managed C++/CLI

Convert System::String^ to char* array

30-Jun-08 6:15

rose196 wrote:
can you give me some example links

No, I can't.

If you do some research (starting at that link), you'll see there's many methods
available for accessing databases from C++. Each has pros and cons.
Choose a method, learn how it works, then I can maybe help.

ADO.NET is probably the easiest to get started with in managed code, but
even explaining ADO.NET here is a bit much to ask.

You'll find tons of working sample code in the documentation.

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

Re: database

Paul Conrad2-Jul-08 18:18

Paul Conrad

2-Jul-08 18:18

rose196 wrote:
how to connect database to .net windows form application

Try googling, or doing a search on this site. www.connectionstrings.com[^] is also very helpful.

"The clue train passed his station without stopping." - John Simmons / outlaw programmer

"Real programmers just throw a bunch of 1s and 0s at the computer to see what sticks" - Pete O'Hanlon

Manfr3d28-Jun-08 10:25

Re: Convert System::String^ to char* array

28-Jun-08 10:25

Hello guys,

I want to read the content of a textbox (a path) and then edit a file at this path.
The type of textbox->Text is System::String^ but file manipulating functions all need char* type parameters. How can I cast the text of the textbox into a char* variable, or are there newer functions than fopen(), fprintf() and so on, which work with managed type variables?

Thanks and best wishes,
Manfred

Luc Pattyn28-Jun-08 11:14

Luc Pattyn

28-Jun-08 11:14

Hi,

in .NET you can do most of not all text processing using the String type; have a look at
the File and/or FileInfo classes.

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Voting for dummies? No thanks. Dead | X|

Re: Convert System::String^ to char* array

leonigah1-Jul-08 20:46

leonigah

1-Jul-08 20:46

array<wchar_t>^ szArray = strPath->ToCharArray();
char buffer[50]={0};
int i = 0;
for each(wchar_t ch in szArray)
buffer[i++] = ch;

Nigah M Manzoor

Re: Convert System::String^ to char* array

Manfr3d2-Jul-08 3:47

'”OFWin”' : undeclared identifier

2-Jul-08 3:47

Thanks, it's working now Smile | :)

hassan8528-Jun-08 10:12

hassan85

28-Jun-08 10:12

It is giving an error undeclared identifier i dont know why ? Confused | :confused:

I am making Win32 Window through WINAPI , WNDPROC, WNDCLASSEX now, in

WNDCLASSEX structure i have define "static LPCTSTR szAppName= L"OFWin""

WindowClass.lpszClassName= szAppName;

So wat to do in order to resolve it. ?

Headers windows.h is included.

Re: '”OFWin”' : undeclared identifier

Mark Salsbery28-Jun-08 12:15

BeforeNavigate2 webbrowser form control

28-Jun-08 12:15

Why is the compiler looking for "OFWin" as an identifier when
"OFWin" is characters in a string?

This compiles for me:

static LPCTSTR szAppName= _T("OFWin");
WNDCLASSEX wce;
wce.lpszClassName = szAppName;

Also...

static LPCTSTR szAppName= L"OFWin"; // only compiles in Unicode builds

should be

static LPCTSTR szAppName= _T("OFWin");  // compiles in Unicode and non-Unicode builds

Mark

Mark Salsbery
Microsoft MVP - Visual C++
Java | [Coffee]

gridDrawer dll

mikobi26-Jun-08 3:44

mikobi

26-Jun-08 3:44

I am using Visual c++ NEt 2005, I need to set the title of my DataGridView when I printed it using gridDrawer dll but I can't.

Who have try to put a title to his printed DataGridView using GridDrawer dll. I need help

Re: gridDrawer dll

led mike26-Jun-08 4:51

led mike

26-Jun-08 4:51

If you are talking about the Article here on CodeProject you should ask the question in the forum at the bottom of the article.

led mike

Xaria25-Jun-08 16:12

Xaria

25-Jun-08 16:12

Can i use a beforeNavigate2 event with a webbrowser form contorl?
I have two forms with webbrowser controls. When I click on a link in webrowser1, the page should be displayed in webBrowser2.
to do this i wish to use beforenavigate2 to cancel the request and then use the url to open in webBrowser2.
How can I accoplish this?

How do you reset StreamReader? There is no seek function.

BuckBrown25-Jun-08 12:20

BuckBrown

25-Jun-08 12:20

Hi. I'm using Visual Studio 2005 C++/CLI. I have a file that has its contents read into an array, one line of the file per element of the array. There may be 10 elements to read or 10,000 elements to read. I would like to define the array size dynamically by reading each line of the file, counting until all the lines are read. Then I want to go back to the begining of the stream but there is no Seek() function. I tried streamReader->Close() and then another streamReader = gcnew StramReader(fileStream) but that doesn't work. Can I reset the streamReader back to the beginning?

Thanks
Buck

Re: How do you reset StreamReader? There is no seek function.

Robert.C.Cartaino25-Jun-08 12:44

Robert.C.Cartaino

25-Jun-08 12:44

I think you can access the Seek method through the StreamReader's BaseStream property. I'm not by a C++ compiler so I can't test this.

Try this out:

FileStream* fs = new FileStream(S"YourFile.txt", FileMode::???, FileAccess::???);
StreamReader* sr = new StreamReader(fs);

sr->BaseStream->Seek(0, SeekOrigin::Begin);

I think you will also need to call sr->DiscardBufferedData() after the Seek or you will get unexpected results.

Re: How do you reset StreamReader? There is no seek function.

BuckBrown26-Jun-08 5:56

BuckBrown

26-Jun-08 5:56

Thanks Robert,

Yes, that works.

The key here is the sr->DiscardBufferedData() otherwise the sr->BaseStream->Seek() function does nothing.

Buck

Executing a programm from my application

Manfr3d25-Jun-08 8:29

25-Jun-08 8:29

Hello guys,

I'm trying to execute a *.exe file from an own win api. Of course I looked through the internet but all i could find was ShellExecute() and CreateProcess() which, for any reason, don't work in VC++2008. Do I need to include any special library files or headers to get access to these functions, or is there another way to start a program from my win api?

Thanks ans best wishes,
Manfred

Luc Pattyn25-Jun-08 8:49

Luc Pattyn

25-Jun-08 8:49

Hi,

if you want to create a process, maybe you should read up on the Process class?

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

Voting for dummies? No thanks. Dead | X|

Mark Salsbery25-Jun-08 9:55

25-Jun-08 9:55

Austrian_Programmer wrote:
Do I need to include any special library files or headers to get access to these functions

ShellExecute()
Header - shellapi.h
Import library - shell32.lib

CreateProcess()
Header - Declared in Winbase.h; include Windows.h.
Library - Use Kernel32.lib.

Manfr3d26-Jun-08 2:36

26-Jun-08 2:36

Thanks, but you need windows.h in both cases.

I tried the ShellExecute() function with the included header and library, but nothing happens, the specified program didn't start.

<br />
#pragma once<br />
#pragma comment(lib, "shell32.lib")<br />
<br />
#include <windows.h><br />
#include <shellapi.h><br />
<br />
// ...<br />
<br />
char *pcOp = "open";<br />
char *pcPath = "calc.exe";<br />
ShellExecute(NULL, (LPCWSTR)pcOp, (LPCWSTR)pcPath, NULL, NULL, SW_SHOWNORMAL); <br />
</shellapi.h></windows.h>

As I run this code I didn't get any error messages but nothing happened.
What am I doing wrong?

led mike26-Jun-08 4:46

led mike

26-Jun-08 4:46

Austrian_Programmer wrote:
As I run this code I didn't get any error messages but nothing happened.
What am I doing wrong?

What was the return value from ShellExecute?

led mike

Mark Salsbery26-Jun-08 6:13

Directshow methods in VC++ Windows forms application

26-Jun-08 6:13

Austrian_Programmer wrote:
ShellExecute(NULL, (LPCWSTR)pcOp, (LPCWSTR)pcPath, NULL, NULL, SW_SHOWNORMAL);

As I run this code I didn't get any error messages but nothing happened.
What am I doing wrong?

Casting char*s to wchar_t*s is not good.

You shouldn't use casts unless absolutely necessary. If it doesn't compile without
the casts, then I recommend looking at the types involved before covering the problem
with a cast.

Mark

bhanu_850925-Jun-08 5:04

bhanu_8509

25-Jun-08 5:04

Can we use the directshow methods in VC++ windows forms application. I have worked in VC++ MFC using Dshow methods and dont know how to use in VC++ Windows forms application. I got linker error when I use the Dshow methods, also I specified all the libraries in Project properties. Please advice.

Many thanks in advance.

Re: Directshow methods in VC++ Windows forms application

Mark Salsbery25-Jun-08 9:56

Re: Directshow methods in VC++ Windows forms application

25-Jun-08 9:56

What are the errors exactly?

Mark

bhanu_850925-Jun-08 23:19

bhanu_8509

25-Jun-08 23:19

1>------ Build started: Project: AV2USB, Configuration: Debug Win32 ------
1>Linking...
1>AV2USB.obj : error LNK2020: unresolved token (0A00000E) IID_IAMStreamConfig
1>AV2USB.obj : error LNK2020: unresolved token (0A00000F) IID_IBaseFilter
1>AV2USB.obj : error LNK2028: unresolved token (0A000011) "extern "C" void __stdcall VariantInit(struct tagVARIANT *)" (?VariantInit@@$$J14YGXPAUtagVARIANT@@@Z) referenced in function "private: void __clrcall AV2USB::Form1::button4_Click(class System::Object ^,class System::EventArgs ^)" (?button4_Click@Form1@AV2USB@@$$FA$AAMXP$AAVObject@System@@P$AAVEventArgs@4@@Z)
1>AV2USB.obj : error LNK2020: unresolved token (0A000012) IID_IPropertyBag
1>AV2USB.obj : error LNK2020: unresolved token (0A000013) IID_ICreateDevEnum
1>AV2USB.obj : error LNK2020: unresolved token (0A000014) IID_ICaptureGraphBuilder2
1>AV2USB.obj : error LNK2020: unresolved token (0A000015) IID_IGraphBuilder
1>AV2USB.obj : error LNK2001: unresolved external symbol IID_IAMStreamConfig
1>AV2USB.obj : error LNK2001: unresolved external symbol IID_IBaseFilter
1>AV2USB.obj : error LNK2019: unresolved external symbol "extern "C" void __stdcall VariantInit(struct tagVARIANT *)" (?VariantInit@@$$J14YGXPAUtagVARIANT@@@Z) referenced in function "private: void __clrcall AV2USB::Form1::button4_Click(class System::Object ^,class System::EventArgs ^)" (?button4_Click@Form1@AV2USB@@$$FA$AAMXP$AAVObject@System@@P$AAVEventArgs@4@@Z)
1>AV2USB.obj : error LNK2001: unresolved external symbol IID_IPropertyBag
1>AV2USB.obj : error LNK2001: unresolved external symbol IID_ICreateDevEnum
1>AV2USB.obj : error LNK2001: unresolved external symbol IID_ICaptureGraphBuilder2
1>AV2USB.obj : error LNK2001: unresolved external symbol IID_IGraphBuilder
1>E:\GUI\AV2USB\Debug\AV2USB.exe : fatal error LNK1120: 14 unresolved externals
1>Build log was saved at "file://e:\GUI\AV2USB\AV2USB\Debug\BuildLog.htm"
1>AV2USB - 15 error(s), 0 warning(s)
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

Re: Directshow methods in VC++ Windows forms application

Mark Salsbery26-Jun-08 6:29