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Re: Parsing a string that contains only one seperator

Ravi Bhavnani12-Dec-01 6:25

Ravi Bhavnani

12-Dec-01 6:25

Stevieslu wrote:
Sorry if this question is a bit stupid...
The only stupid question is the one not asked! Here's how:

char szBuffer [LARGE_ENOUGH_TO_HOLD_STRING];
CString strMyString = "Whatever";

  szBuffer [0] = '\0';
  if (strMyString.GetLength() < LARGE_ENOUGH_TO_HOLD_STRING) {
     strcpy (szBuffer, strMyString.GetBuffer (0));
     strMyString.ReleaseBuffer();
  }

/ravi

"There is always one more bug..."
ravib@ravib.com
http://www.ravib.com

this-> question

Frank Liao29-Oct-01 9:52

Frank Liao

29-Oct-01 9:52

Hi All,

I was just wondering about something that has been bugging me ever since I saw something like this in Java. In practice, which type of statement would be more preferable if you were to call a class function inside the same class in C++?

class Object {
  void func1() { this->func2() }
  void func2() {}
};

class Object {
  void func1() { func2() }
  void func2() {}
};

Is there any performance differences between the two? Confused | :confused:

Also, I apologize if this code might look wrong. I just wanted a conceptual opinion. Smile | :)

Frank

Re: this-> question

Carlos Antollini29-Oct-01 9:56

Carlos Antollini

29-Oct-01 9:56

No direrences....

Best Regards...

Carlos Antollini.

Re: this-> question

Tomasz Sowinski29-Oct-01 10:18

Tomasz Sowinski

29-Oct-01 10:18

There's no performance difference. IMHO, you only need 'this->' when one of the method parameters has name colliding with name of another data member. In the example below, the parameter 'foo' hides the member 'foo', so you need to explicitly qualify it with 'this'. Of course, you can rename the SetFoo parameter 'foo' to 'theFoo', in such case there's no need for explicit 'this'.

class obj
{
public:
	void SetFoo(int foo) { this->foo = foo; }
	int GetFoo() const { return foo; }
private:
	int foo;
};

Tomasz Sowinski -- http://www.shooltz.com

Window's API errors

29-Oct-01 9:11

I'm new to c++ and wanted to implement a few api calls into a test project. Unfortunately, every call fails w/ the unresolved external symbol error. Why? I include windows.h and give the functions all required parameters. Here's a sample-->
#include <windows.h>

int main()
{
HWND hwnd=NULL;

ShellExecute(hwnd, "open","http:\\www.google.com",NULL,NULL,SW_SHOWDEFAULT);

return 0;

}

and i receive these errors-->
main.obj : error LNK2001: unresolved external symbol __imp__ShellExecuteA@24

Debug/load.exe : fatal error LNK1120: 1 unresolved externals

Re: Window's API errors

Christian Graus29-Oct-01 9:20

Christian Graus

29-Oct-01 9:20

from MSDN:

Header: Declared in Shellapi.h.
Import Library: Shell32.lib.

You've obviously got the header, try adding shell32.lib to your libraries list in the options for your project.

Christian

After all, there's nothing wrong with an elite as long as I'm allowed to be part of it!! - Mike Burston Oct 23, 2001

Re: Window's API errors

Michael P Butler29-Oct-01 9:20

Michael P Butler

29-Oct-01 9:20

You need to link your application with Shell32.lib.

Michael Smile | :)

Access 2000, DAO version ...

Hadi Rezaee29-Oct-01 7:55

Hadi Rezaee

29-Oct-01 7:55

Hi all,
I want to know, What is Access 2000, DAO version ?
Because, in one of MSDN article about DAO:
[B]
"This article describes how to create an Access 2000 (Jet 4.0) database in Visual C++ 6.0."

and other part of that article:

"DAO 3.6 is installed with Office 2000."

Does Access 2000 install DAO 3.6 and DAO 4.0 ?
For using DAO 4.0 in my programs, i must write below source code ?

AfxGetModuleState()->m_dwVersion = 0x601;

My month article: Game programming by DirectX by Lan Mader.
Please visit in: www.geocities.com/hadi_rezaie/index.html

Hadi Rezaie Big Grin | :-D

Re: Access 2000, DAO version ...

Carlos Antollini29-Oct-01 8:51

Carlos Antollini

29-Oct-01 8:51

The problem is that MFC supports only dao 3.0 but when you install Access you will have the 3.6 version of DAO.
Okey, when tou initialize the engine of dao with afxdaoinit mfc wil set access 3.0 but you can use dao 3.6 that you have in your machine because it was installed by access 2000, and for that you can use it you must set AfxGetModuleState()->m_dwVersion = 0x601...

That's it.
If you need a better explanation please looking for a issue of MSJ of year 2000.... (I think that in Febraury or march) where Paul Dilascia explain the problem....

best Regrards

Carlos Antollini.

Re: Access 2000, DAO version ...

Steen Krogsgaard29-Oct-01 22:37

Steen Krogsgaard

29-Oct-01 22:37

Access2000 installs DAO 3.6 and Jet 4.0 - not the same thing. DAO is a set of COM objects that let you use the Jet db engine (which Access2000 is a front-end for).

DAO and Jet are related as ODBC ans SQL Server is - if that makes it any clearer Confused | :confused:

Cheers
Steen.

"To claim that computer games influence children is rediculous. If Pacman had influenced children born in the 80'ies we would see a lot of youngsters running around in dark rooms eating pills while listening to monotonous music"

Re: Access 2000, DAO version ...

Steen Krogsgaard29-Oct-01 22:37

Steen Krogsgaard

29-Oct-01 22:37

Access2000 installs DAO 3.6 and Jet 4.0 - not the same thing. DAO is a set of COM objects that let you use the Jet db engine (which Access2000 is a front-end for).

DAO and Jet are related as ODBC and SQL Server is - if that makes it any clearer Confused | :confused:

Debug assertion failed getting itemtext from listview

Kuniva29-Oct-01 7:28

Kuniva

29-Oct-01 7:28

I wanted to get the text from an item in a listview control on my main dialog window but it gives me a debug assertion error:

CMyDlg dlg;
m_pMainWnd = &dlg;
int nResponse = dlg.DoModal();
if (nResponse == IDOK)
{
CString Data = dlg.m_MyListcontrol.GetItemText(0,1);
}

Any ideas why??
The item in the list control exists, no doubt about that but is it maybe because the main window has already closed or something?
How do i do this?

Thanks

Kuniva

Re: Debug assertion failed getting itemtext from listview

J Patel29-Oct-01 7:56

J Patel

29-Oct-01 7:56

You are checking the value after the dialog has been destroyed hence all child controls are also destroyed. GetItemText does a SendMessage to the hWnd of the ListControl which no longer exists hence you get the assertion.

Save the value on the OnOK handler of the dialog to a CString member variable and then you'll be fine.

<br />
// In dialog<br />
CMyDlg::OnOK()<br />
{<br />
  m_strData = m_MyListControl.GetItemText(0,1);<br />
}<br />
<br />
<br />
// modified Original code<br />
CMyDlg dlg;<br />
m_pMainWnd = &dlg;<br />
int nResponse = dlg.DoModal();<br />
if (nResponse == IDOK)<br />
{<br />
CString Data = dlg.m_strData;<br />
}<br />
<br />

HTH

Jignesh

Re: Debug assertion failed getting itemtext from listview

Alvaro Mendez29-Oct-01 9:45

Alvaro Mendez

29-Oct-01 9:45

Good explanation. Smile | :)

Regards,
Alvaro

Re: Debug assertion failed getting itemtext from listview

J Patel29-Oct-01 7:57

J Patel

29-Oct-01 7:57

Oops, don't forget to call the CDialog::OnOK after you save the value - in my prev post.

ON_EVENT

29-Oct-01 6:46

Quick question,

I'm trying to use ON_EVENT and I can't seem to figure out what the dispid is.. I pulled the following from MSDN.. I cant make any sense of "dispid".. How can I figure out what value I need to enter for the dispid?

Thanks,
Rob Jones

ON_EVENT( theClass, id, dispid, pfnHandler, vtsParams )

Parameters

theClass

The class to which this event sink map belongs.

id

The control ID of the OLE control.

dispid

The dispatch ID of the event fired by the control.

pfnHandler

Pointer to a member function that handles the event. This function should have a BOOL return type, and parameter types that match the event's parameters (see vtsParams). The function should return TRUE to indicate the event was handled; otherwise FALSE.

vtsParams

A sequence of VTS_ constants that specifies the types of the parameters for the event. These are the same constants that are used in dispatch map entries such as DISP_FUNCTION.

Here is a sample of what I have.. How do I know what to put in for the dispid?
I used a "1" in this example and it works.. But if I add another control I can't seem to use the "1" again.

BEGIN_EVENTSINK_MAP(CSkinDemoDlg, CDialog)
    //{{AFX_EVENTSINK_MAP(CSkinDemoDlg)
	ON_EVENT(CSkinDemoDlg, IDC_OK, 1 /* Click */, OnClickOk, VTS_NONE)
	ON_EVENT(CSkinDemoDlg, IDC_SKINSCROLLBAR1, 1 /* Change */, OnChangeSkinscrollbar1, VTS_NONE)
	//}}AFX_EVENTSINK_MAP
END_EVENTSINK_MAP()

Rob

Painting an icon into bitmap

krausest29-Oct-01 5:57

krausest

29-Oct-01 5:57

Hi,

I've tried to work with icon with .net, but I didn't manage to get the alpha information right. Thus I decided to look at the problem from straight c++ and gdi+.
I want to draw the icon e.g. from "a:\" into a bitmap. Doing so will ignore the alpha portion of the image.

Here's the painting code (it's a standard mfc app. Just add it into your view's OnDraw):

CPaintDC dc(this);

Graphics g(dc);

SHFILEINFO info;
DWORD_PTR hTcdf = SHGetFileInfo("a:\\",0,&info, sizeof(info), SHGFI_SYSICONINDEX | SHGFI_LARGEICON |SHGFI_ICON);
m_icon = info.hIcon;

Bitmap bit(50,50,PixelFormat32bppARGB);
PixelFormat pf=bit.GetPixelFormat();
assert(pf==PixelFormat32bppARGB);
Graphics g2(&bit);

HDC bdc=g2.GetHDC();

DrawIconEx(bdc,0,0,m_icon,0,0,0,NULL,DI_NORMAL);
g2.ReleaseHDC(bdc);

g.DrawImage(&bit,40,30);

DrawIconEx(dc,40,100,m_icon,0,0,0,NULL,DI_NORMAL);

The latter icon is drawn correctly the former not. Can somebody help?

Thanks,
Stefan

getting listview item text

Kuniva29-Oct-01 5:56

Kuniva

29-Oct-01 5:56

How do i get the text of an item in a listview control and possibly other subitems?

Kuniva

Want, take, have.
(oh btw, best way of learning some language is by looking at examples, start large!) :p

Re: getting listview item text

Carlos Antollini29-Oct-01 6:09

Carlos Antollini

29-Oct-01 6:09

With CListCtrl::GetItemText
For example you have CString GetItemText(Item, subItem)

Best Regars....

Carlos Antollini.

c++ forums/contacts and help?

CrazyJim29-Oct-01 5:37

CrazyJim

29-Oct-01 5:37

I am looking for help on stuffing the keyboard. So like. No one here knows exact code to stuff like an "A" in the keyboard... Where are other good places to turn for help? I've been stuck on this for 3 days.

Re: c++ forums/contacts and help?

Carlos Antollini29-Oct-01 5:50

Carlos Antollini

29-Oct-01 5:50

what do youn need?

Regards

Carlos Antollini.

Re: c++ forums/contacts and help?

CrazyJim29-Oct-01 7:39

CrazyJim

29-Oct-01 7:39

I need to be able to stuff the keyboard buffer, alla keybd_event(), but keybd_event doesn't work on several applications. I have considered sendinput(), but its windows 98 specific and I would kind of like 95 users to use my program.... I guess I should spend another 5 hours trying to figure out sendinput... It is likely it won't even work.

I was wondering if there was anyone that knew inline assembly to solve this, or if anyone just knew an ok solution... I'm mid stride through a huge "otherwise fun" application, and I get hit with a brick to the head with keybd_event() not working well.

Since I asked this question before, and no one knew... I was wondering if anyone knew of more Visual C++ forums, or maybe a forum for the inline Aplha assembler langauge.... I spent a few hours yesterday and only found like 2 forums.

Re: c++ forums/contacts and help?

Carlos Antollini29-Oct-01 7:51

Carlos Antollini

29-Oct-01 7:51

you tried with CWnd::OnChar?
But you have OnKeyUp and OnKeyDown...
I think that OnChar is better bucause you can trap All keyboard events...

OnChar is the implementation of WM_CHAR Message....

I Hope to help you...

best Regards.... Big Grin | :-D

you have a nice day!!!

Carlos Antollini.

Re: c++ forums/contacts and help?

Tomasz Sowinski29-Oct-01 9:32

Tomasz Sowinski

29-Oct-01 9:32

I have considered sendinput(), but its windows 98 specific and I would kind of like 95 users to use my program

I was wondering if there was anyone that knew inline assembly to solve this

I was wondering if anyone knew of more Visual C++ forums, or maybe a forum for the inline Aplha assembler langauge....

I don't understand. First you write that you need Win95 compatibility, then you want to solve the problem with Alpha inline assembly?

Tomasz Sowinski -- http://www.shooltz.com

Re: c++ forums/contacts and help?

Rassman30-Oct-01 3:12

Rassman

30-Oct-01 3:12

I think the trouble here is that you seem to be asking how interrupt the stdin to replace whats coming in with the letter 'A'. But you don't simply want to receive the input and replace it within your program, it seems to want to do it on a system wide level. The suggestion to use the OnChar should be the answer otherwise.

Windows would be extreemly insecure if it allowed this sort of thing.

We do it for the joy of seeing the users struggle.

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