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This is somewhat of a difficult problem to explain, so please bare with me.
I have a class which is resposible for the allocation of an array of 4 structs. This class is a base class through which I can retrieve a pointer to the array and modify the struct members. Due to the nature of the program, I need access to all the structs ( for each instance of the class ). So, In the base class I created a static vector of structs, each time an instance of the class is created it add 4 new members to this static vector.
This is where my problem lies. Each instance needs to know exactly where in the vector it's 4 structs are located. This could be easily solved by recording the index they were inserted. But lets say I create 3 instances ( 12 structs in the vector ), then I delete the first instance. I would need to erase those 4 members from the vector which would cause the next instance to index the wrong value, and the third to be past the end.
I need some way to keep track of those 4 structs without needing to worry about instances being added or deleted. Any ideas?
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Create a hashtable of vectors and make a pointer to your base class the key. Then, you can use 'this' to access each vector, to delete it in your destructor, or to access it otherwise.
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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Thanks for the idea. I guess 'this' does have it's uses after all.
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There is a fundamental flaw in your design, as the static code must keep track of who exists and who does not, and apparently it is not designed to do that.
In the short run I would recommend using a map container (STL), that way you are not using offsets. Instead you are using a key that specifies the location, which simplifies everything considerably. Note that a map is not a hash table, but is a red & white tree (I think); not that it matters.
INTP
"Program testing can be used to show the presence of bugs, but never to show their absence."Edsger Dijkstra
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Hi
Please help me.
#sanroop#
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i am reading a file in win32 now my file data is stored in the WCHAR array buffer
now I want to put this data orderwise in the listview.
for that i need to convert WCHAR to string.
Environment .net(unicode).
the xml file is below.
<xml>
<FILElist>
<listitem type="file" order="1" >
<filename>C:\Documents and Settings\Administrator\Desktop\MediaFiles\TT.wmv</filename>
<Extension> khuntapada </Extension>
<size>494KB </size>
<duration>00:00:38</duration>
<bitrate>103kbps</bitrate>
<type>Windows Media Audio/video file</type>
<modifieddate>12/10/2005 </modifieddate>
<protected>completed/incompleted</protected>
</listitem>
<listitem type="dir" order="2">
<path>C:\Documents and Settings\Administrator\Desktop\MediaFiles </path>
</listitem>
</FILElist>
</xml>
source file
WCHAR szBuff[5000];
hFile=CreateFile ( L"c:\\Encoder_3.XML"
, GENERIC_READ | GENERIC_WRITE
, FILE_SHARE_READ
, NULL
, OPEN_EXISTING
, FILE_ATTRIBUTE_NORMAL
, NULL
);
if(hFile == INVALID_HANDLE_VALUE)
{
MessageBox(0,_T("File is not exist"),_T("Create File"),0);
}
else
{
MessageBox(0,_T("File is exist"),_T("Create File"),0);
}
bool bSucced=ReadFile(hFile,&szBuff,5000,&dwRecvLen,NULL);
szBuff[dwRecvLen] = '\0';
size_t len = wcslen(szBuff) * sizeof(WCHAR);
char* tempOutFile = new char[len];
WideCharToMultiByte(CP_ACP,0,szBuff,-1,tempOutFile,(int)len,NULL,NULL);
//std::string str1 = tempOutFile;
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Hello to all...
Please suggest me neccessary stuff about client server programming..
I need to build an application where I have some exe file (say A.exe) on the server...
Client sent a path of a file(say B.exe) on their machine to server..
Server modifies that file(B.exe) on the cliend end...using the Exe(A.exe).
I hope request is clear..
Bye...
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Hi,
I was looking about C++ crtification but didn't really find anything. So, I wonder if someone can help me telling about how to be a certified C++ Professional.
Thanks very much
C++Prog
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Certification doesn't mean anything, and I've NEVER been asked if I was "certified". Get experience and demonstrate some talent.
"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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I've heard it suggested you may be certifiable, is that the same ? :P
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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Close. 
"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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celllllllll wrote: So, I wonder if someone can help me telling about how to be a certified C++ Professional.
Hardly[^]
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Certifications are a joke, they are a waste of time. They prove nothing, apart from a willingness to pay for a test over and over, until you pass it.
Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
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Christian Graus wrote: Certifications are a joke
And Microsoft is Big. So Microsoft Certified means a Big Joke? 
Nobody can give you wiser advice than yourself. - Cicero
ப்ரம்மா
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Yep, probably
Christian Graus - C++ MVP
'Why don't we jump on a fad that hasn't already been widely discredited ?' - Dilbert
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All the certificate shows is that you know how to take and pass a test. It doesn't show you are good at what you do. The chances are you will never be asked for it.
I'm a certified teacher. I spent years and a lot of money to get my certificate. Does that make me a good teacher? Does it prove I can handle rugrats nibbling away at my ankles? I think not. I have never EVER been asked for my qualifications, the only thing I do get asked for is my experience.
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Hi,
The test case 30(“Verify the application is Restart Manager Aware”) for Certified for Vista tells "The application should shut down quietly via the RMShutdown API".
It's means I've to handle WM_QUERYENDSESSION in my application and respond TRUE back to OS.
The application should be in on idle. My application is MFC MDI application.
- The question is : where(CMainFrame or in MyApp::OnIdle()) and how(I've to return TRUE back) should I handle this.
Thanks for the any sutable information.
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oleg63 wrote: It's means I've to handle WM_QUERYENDSESSION in my application and respond TRUE back to OS.
TRUE is the default return value. Unless your application needs to return FALSE, you don't need to do anything.
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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This has been a problem of mine for years.
It appears to be compiler specific which is why I put it in this section.
Run this piece of code
double test = 3.0/10.0;
The result of test is .299999999999999
I know why this happens. I was just wondering how some of you have solved this problem.
Thanks for any input
George W
Software Developer
www.zsystems.ca
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IGeorgeI wrote: I know why this happens. I was just wondering how some of you have solved this problem.
If you know why it happens, then you must also know it has no solution. Floating-point numbers behave that way on binary machines.
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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Of course but when you are dealing with high precision numbers, you have to implement workarounds to solve the problem.
I was just wondering how others have handled it. You simply cannot leave it like that when dealing with mathematical engines written in c++. The error will carry through and get worse. So I just wanted to see what others are doing.
For your information, the c# compiler does solve the problem and does give you to correct base 10 answer of .30
George W
Software Developer
www.zsystems.ca
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IGeorgeI wrote: For your information, the c# compiler does solve the problem and does give you to correct base 10 answer of .30
Perhaps it makes use of some sort of epsilon value. See here for more.
"Approved Workmen Are Not Ashamed" - 2 Timothy 2:15
"Judge not by the eye but by the heart." - Native American Proverb
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