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Hello,
I would suggest that you don't need the delete.
If your example looked like this:
int* inptr = NULL;
but if you allocate memory with the keyword 'new'
then you should 'delete' it form the heap.
So you can remember new and delete belong together.
Greetz
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The whole thing is bad form.
First, a pointer should be set to NULL, not 0. This is more for practical readability than anything else.
Second, you should not delete a pointer that hasn't been allocated. I know, modern compliers let you do it, and it's supposed to be safe, but it's bad practice.
Lastly, your variable names quite frankly suck.
The whole thing should read like this:
T* p = NULL;
if (p != NULL)
{
delete p;
p = NULL;
}
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001
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Hello all ,
i have made 4 ui threads in my application and various instances of these threads are running at same time. There may be 100 or 200 instances running.
what i want to knw is how can i close all these thread together rather closing them one by one.
Can anybody help me in this....
Thanks in advance
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I am developing a software in which,
each menu opens a panel(dialog) and user is suppose to not access
the other menu ,unless he closes dialog. So by the time one panel is active ,it is required to deactivate entire menubar.
I am using SDI and modified default menu bar for same.
I was not able to find any method to directly deactivate.
But whatever I found that is also not working.
My entire toolbar I was able to disable,but not menu bar.
Also I like to know how to disable individual button of toolbar.
void CMainFrame::OnAddCustomer()
{
CToolBarCtrl& ctb = m_wndToolBar.GetToolBarCtrl();
ctb.EnableWindow(FALSE);
ctb.PressButton(ID_ADD_CUSTOMER,true);
CMenu* cmu = this->GetMenu();
UINT ui = cmu->EnableMenuItem(ID_ADD_CUSTOMER,MF_DISABLED);
|| ART OF LIVING ||
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You could use MFC command enablers. This should enable/disable both toolbar and menu items...
afx_msg void OnUpdateDbconnect(CCmdUI* pCmdUI);
...
BEGIN_MESSAGE_MAP(CMainFrame, CFrameWnd)
ON_UPDATE_COMMAND_UI(ID_ADD_CUSTOMER, OnUpdateAddCustomer)
END_MESSAGE_MAP()
...
void CMainFrame::OnUpdateAddCustomer(CCmdUI* pCmdUI)
{
if (...some condition...)
pCmdUI->Enable(FALSE);
else
pCmdUI->Enable(TRUE);
}
See the ON_UPDATE_COMMAND_UI/ON_UPDATE_COMMAND_UI_RANGE macros in the docs.
You can also disable thw main window
EnableWindow(FALSE);
That's what MFC does to simulate modal dialogs.
Mark
Mark Salsbery
Microsoft MVP - Visual C++
This episode brought to you by the number 3
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I want to control the avi write action by query the IAMStreamControl interface of input pin in pAviMux, see below:
IAMStreamControl *pSC = NULL;
hr = pMuxPin01->QueryInterface(IID_IAMStreamControl, (void **)&pSC);
hr = pSC->StartAt(&rtStart, 0); //rtStart = 3 seconds
hr = pSC->StopAt(&rtStop, FALSE, 0); //rtStop = 9 seconds
hr = pMediaControl->Run();
when I set the parameter of StartAt() as NULL, it works OK,
the pMuxAvi stop the writing at rtStop time. however,
when I give a rtStart parameter to StartAt() function,
the pMuxAvi write a corrupt avi file which is only 127kb in size.
what's wrong with the StartAt() function? please help.
-- modified at 6:02 Saturday 14th July, 2007
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hello
i like to recieve data from digitizer or a tablet connected to my computer through usb .
how can i do that.
these data come from moement of pen over the tablet , like speed of writing, depth, degree of the pen , and others
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Normally, you should have a driver that is supplied with this device. To 'communicate' with this device from your code, you need to get a handle to this driver (using CreateFile) and then you will be able to use ReadFile and WriteFile operation. You probably want to do some specific things with the driver in which case you can call DeviceIOControl and supply some specific code.
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Thank you for your help.
i well try to do what you tell me.
i installed the driver but i see there are 4 or more DLL files.
can you tell me how can i know the suitable file among them for me to read from it the data
if you have other advices in using these commands (FreateFile ReadFile/WriteFile, DeviceIOControl)write to me i
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Hi,
I can able to connect Ms_word to VC++ MFC application and can write text in that. But I want to know how can i insert image in ms-word using MFC. If you help me, it will be great.
Actually i refered
http://support.microsoft.com/kb/q238611/[^] this site to embed Ms-word to MFC
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How can i import jpeg images into workspace of an application?
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Right click on the Resource View of your project and select Add Resource and click Import button after select your image file(jpg) you see a other window "Custom Resource Type" you must type a name for this resource and click ok.
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A char is a single character. You'd be better off storing the file name in a char array.
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Hi to all,
I am using VC++ 2005 and trying to employ LiteUnzip a series of ZIPPED files but once I retrieve the file names within the ZIP I would like to decompress them using an alternate path, so I am trying to override ze.Name and give it a path which has been defined within a String.
Take a look at the code below to get an idea where I'm coming from:
private: void UnZIP(String^ file,String^ source, String^ target)<br />
{<br />
HUNZIP hz;<br />
ZIPENTRY ze;<br />
String^ inFile;<br />
String^ outFile;<br />
String^ fileName;<br />
DWORD numitems;<br />
<br />
inFile = source + file;<br />
pin_ptr INFILE = PtrToStringChars(inFile);<br />
UnzipOpenFile(&hz,INFILE,0);<br />
<br />
ze.Index = (DWORD)-1;<br />
UnzipGetItem(hz,&ze);<br />
numitems = ze.Index;<br />
<br />
for(ze.Index = 0;ze.Index < numitems + 1;ze.Index++)<br />
{<br />
UnzipGetItem(hz,&ze);<br />
<br />
String^ systemstring = gcnew String(ze.Name);<br />
fileName = Path::GetFileName(systemstring);<br />
delete systemstring;<br />
<br />
outFile = target + "\\" + fileName;<br />
ze.Name = outFile; <---- Need to find a way to convert a String to an acceptable type.
UnzipItemToFile(hz,ze.Name,&ze);<br />
}<br />
<br />
UnzipClose(hz);<br />
}
Cheers
Fritzables.
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The following file is a sample from the book <thinking in="" c++="">,
but it cann't be compiled correctly in VC2005, please help me.
#ifndef TSTACK2_H
#define TSTACK2_H
template<class t=""> class Stack
{
struct Link
{
T* data;
Link* next;
Link(T* dat,Link* nxt)
:data(dat),next(nxt)
{
}
}* head;
public:
Stack():head(0)
{
}
~Stack();
void push(T* dat)
{
head = new Link(dat,head);
}
T* peek() const
{
return head ? head->data ;
}
T* pop();
class iterator;
friend class iterator;
class iterator
{
Stack::Link* p;
public:
iterator(const Stack<t>& tl):p(tl.head)
{
}
iterator(const iterator& tl):p(tl.p)
{
}
iterator():p(0)
{
}
bool operator++()
{
if (p->next)
p = p->next;
else p = 0;
return bool(p);
}
bool operator++(int)
{
return operator++();
}
T* current() const
{
if(!p) return 0;
return p->data;
}
T* operator->() const
{
require(p!=0,
"PStack::iterator::operator->returns 0");
return current();
}
T* operator*() const
{
return current();
}
operator bool() const
{
reutrn bool(p);
}
bool operator == (const iterator&) const
{
return p==0;
}
bool operator!=(const iterator&) const
{
return p!=0;
}
};
iterator begin() const
{
return iteraotr(*this);
}
iterator end() const
{
return iterator();
}
};
template<class t=""> Stack<t>::~Stack()
{
while(head)
delete pop();
}
template<class t=""> T* Stack<t>::pop()
{
if (head==0) return 0;
T* result = head->data;
Link* oldHead = head;
head = head->next;
delete oldHead;
return result;
}
#endif
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Put typename in front of Stack::Link to help the compiler to deduce Stack::Link as a type;
class iterator
{
typename Stack::Link* p;
--
=====
Arman
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Thank you very much. The problem has been solved.
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Developed a problem linking, merely by moving code to a New Directory.
Compiler version VCP6.0. First it complained about Linking error 2005, Same functions tried to link to MSVS42D.lid and 'nafxcwd.lib'. Solved this in the end by explicitly excluding 'nafxcwd.lib'. Compiles and links fine, but when trying to run in debugger states that there is no debug info included in the file.
Anyone any idea's?? 
LateNightsInNewry
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yup you need to copy over the pdb files and place them where the debugger can find the debug symbols.
from the menu: tools ---> options
in the dialog select debugging -->symbols
locate the symbols files and make sure you're pointing to them!
Yours Truly, The One and Only!
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Thanks,
Tried that, I'm using MSDevStudio 97 and VCPP5.00 (NOT 6.00 as I erroneously stated earlier) I've got only one pcb file: 'vc50.pdb' Tools->Options is a property sheet. Under the Debug tab is an entry 'symbols' which consists of a checkbox, (which is checked), and No way of pointing anything to it.
None of the other tabs appears to have entries which relate to the subject.
The other repository of settings is Build->Settings. Again, nothing of apparent interrest, safe to say that all paths seem to point where they should. vc50.pdb is in the debug directory, along with the excecutable.
Full rebuilds had been tried at every step in first instance, but to no avail.
This file vc50.pdb is where the trouble started. An alternative name cannot be specified, so when trying to develop a suite with several executables, and a number of dll's, there appears to be no way of assembling the lot in a single arena. 
LateNightsInNewry
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In addition to NightOwl's response, you may (or not) need to do a full rebuild - I'm not sure
but maybe the PDB files store complete paths.
Mark
Mark Salsbery
Microsoft MVP - Visual C++
This episode brought to you by the number 3
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Thanks,
Tried that, but see my reply to NightOwl above
Regards,
LateNightsInNewry
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Hi guys, this is my first post here.
Quick, maybe stupid question, just the way I'm doing this doesn't seem right.
I'm doing an assignment that manipulates and generates some genealogy data and
I'm having a problem figuring out for this part if my code is correct.
This is the assignment prompt for specific part i'm having a problem with:
A default constructor with three arguments (in the same order listed above) that sets the three data members to the values of the arguments. Each argument should be given a default value of 0 in the method prototype.
This is the coding I currently have for that declaration that I'm unsure of:
Date(int day = 0, int month = 0, int year = 0);
Any help here would be greatly appreciated, want to make sure I get this assignment right after
the grades on the last couple! Haha
Thanks guys.
mr. chips
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