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There is no general way to do this. While in some cases possible, by examining debug information for example, it is not possible in all cases and isn't efficient. It's not really in the spirit of the language, which is based on static typing. Perhaps if you describe the specific problem your trying to solve I (or someone else) can be of more help.
In C++ casting to void* like this:
(void*)p
Is an outdated (because it isn't explicit) way of doing this:
reinterpret_cast<void*>(p)
Steve
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You don't want to say I'm outdated, do you?!!
Thanks.
what I want to do is to write a class, that needs to save it's input to a file, without a need to know what is the type, AND, the information be changable to modify the file by hand.and also loadable later on.
( I wanted to write a setting class, with these 2 function:
mySetting.Save((void*)settings);
mySetting.Load((void*)settings)
)
(I'm not going to save binary info to file, and read it again, I know this is easy!)
//This is not a signature
while (I'm_alive) {
printf("I Love Programming");
}
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If I understand you correctly you want to load or save any type with calls such as this:
int Type1;
double Type2;
MyStruct Type3;
mySettings.Save(Type1);
mySettings.Save(Type2);
mySettings.Save(Type3);
mySettings.Load(Type1);
mySettings.Load(Type2);
mySettings.Load(Type3);
In C++ you could do this with template functions:
class CSettings
{
public;
template<class T> void Save(T& SaveMe)
{
SaveTheData(reinterpret_cast<void*>(&SaveMe), sizeof(SaveMe));
}
template<class T> void Load(T& LoadMe)
{
LoadTheData(reinterpret_cast<void*>(&LoadMe), sizeof(LoadMe));
}
};
Steve
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I know templates abit, but problem is not to send different type of data to a class, or function.
It's to save a data structure elements, while we don't know it's elements type or their size. so problem is to find the data type encapsulated in a structure.
anyway thank you very much for your contribution.
//This is not a signature
while (I'm_alive) {
printf("I Love Programming");
}
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I've heard something of RTTI (run time type information), and just this word!
If this is the soloution, I wanted to see how can we enable it in our compiler, and how can we use it?
//This is not a signature
while (I'm_alive) {
printf("I Love Programming");
}
-- modified at 7:11 Saturday 25th February, 2006
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RTTI only works on polymorphic types (types with virtual functions). It doesn't give layout information.
Steve
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So, it seems that I should forget getting such information!,hoping "C/C++" designers think about this issue on later standards!! (If they think about it's usage, it's great usage to create independent classes or functions)
Thnk's alot to all the guys helping me, out there.![Rose | [Rose]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/rose.gif)
Thank you very much indeed for your time and attention
//This is not a signature
while (I'm_alive) {
printf("I Love Programming");
}
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Hamed Mosavi wrote: So, it seems that I should forget getting such information!,hoping "C/C++" designers think about this issue on later standards!! (If they think about it's usage, it's great usage to create independent classes or functions)
just don't try to solve you problem of design with another problem of design... if cant do the job with C/C++, it is simply because you haven't oriented you program for that language...
sorry, it's not an issue to consider in further standards, C/C++ are simply not java/C#...
TOXCCT >>> GEII power
[toxcct][VisualCalc 2.24][3.0 soon...]
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Hi,
I've not been working with java or C#.
I just wanted to ask you, Do these languages solve these type of problems?
Furthermore, why giving information about a data type at compile time is not suitable for C/C++ ? I expect an object oriented programming language to give me the ability to write independent classes, is it too much?
(I accept the fact that it is not good for C/C++ to give me these infomation at runtime, you are absolutely right .)
Thank you for your great kindness![Rose | [Rose]](https://www.codeproject.com/script/Forums/Images/rose.gif) . You pay the most attention. Excuse me if my english is bad .
//This is not a signature
while (I'm_alive) {
printf("I Love Programming");
}
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Hi,
to answer your question, both languages have a mechanism to do wath you wanted.
In C# its called reflection. You can ask a type(class) which members it has at runtime.
Hamed Mosavi wrote: Furthermore, why giving information about a data type at compile time is not suitable for C/C++ ?
C++ doesn't have this for a few good reassons.
a. Its slow
b. It use more memory
c. hence there is no simple memory to a plain 'c' structure translation
Altough c++ doensn't have this. You can create it if you really need/want to.
But there is another approach you might consider. I guess you want to save data from
the memory to a file or vice versa. This is called persistence, or like MFC calls it
Serialisation. This method allows just the thing you want.
You can use there framework (CFile, CArcive) to implement the serialisation you need.
Or you can create your own using this concept. It differs from you concept to a more
OO solutiuon.
Your solution needed one class who knows everything about all classes (this is alsoo
nessecary in c#). When adding a new class you never know if there are restriction on
what to save to file (for instance, void pointer list, function pointers, temporary members)
In the more OO solution, everey class knows how to save/load itself too an archive or
other class object that handles binary data to be saved or loaded to file and memory.
In the second solution, when adding a new class you only need to implement the
save/load function for that class and everything works without problems.
codito ergo sum
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Thank you very much.
Finally one programmer, just get what I needed. Thank you very much.
It's really kind of you. (If you want the fact, I always use CStdioFile, but never used serialization already). However I'm still not sure about the fact that can I bring back my data from a file to a structure with an unknown data elements, and beside the file tobe a text not a binary, but your solutions and information about C# were elegant. Thank you again and again.
I will check to find the best design, If I get a good approach, I'll put this class here in CP.
Thank you.
//This is not a signature
while (I'm_alive) {
printf("I Love Programming");
}
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I think I found a solloution,I'm trying to see if it works.
I'll be offline for some days, perhaps!
 ;)
//This is not a signature
while (I'm_alive) {
printf("I Love Programming");
}
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After seeing the new Office color picker, I began thinking about extending the notion of custom colors to named color sets. The user would select colors into the set of custom colors, and then optionally could save the custom colors to a named color set. The named color sets would be displayed in the color picker directly above the custom colors. (See my article for a screenshot of how it looks now).
Opinions? Comments?
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If you could save a collection of colors by name and then name each color in the collection, that might be useful in some situations.
One situation, for example, might be in a sprite editor. You would name the color collection with the sprite's name, let's say 'Main Battle Tank' and then you could name each color - tracks, engine, barrel, gun, etc. Then these saved color files could be used by anyone doing the graphics editing, if the sprite required updates.
Well, there's my 2 cents.
People that start writing code immediately are programmers (or hackers), people that ask questions first are Software Engineers - Graham Shanks
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Hi
Please give details about socket communication in VC.
thanx in advance
by
KK
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U can use CSocket class if u have the MFC support
nave
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http://www.codeproject.com/internet/
"Opinions are neither right nor wrong. I cannot change your opinion. I can, however, change what influences your opinion." - David Crow
cheers,
Alok Gupta
VC Forum Q&A :- I/ IV
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Hi All,
I am getting an error message saying
"LoadLibrary (abcd.dll failed) - Recursion too deep, Stack overflowed" while registering a COM dll. Can anyone tell me what the problem could be?
Thanks and Regards,
Anil
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I would try if you can load the dll with depends - tool (part of sdk).
This tool will show you if all dependend dll's can be loaded and will report which dll is missing.
Another thing is trying to register the wanted dll by using commandline tool regsvr32 dllname
This will register the com components in registry.
Your dll may tries to register itself when loaded.
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This is only happening when im using a particular function from a library linked to this dll.
Can anyone tell me what the reason could be?
Thanks and Regards,
Anil
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Hello all,
Is there a way to checkpoint a windows process(User Process),rather than just suspend/resume.
What is the core API to be used?
Mention websites which will be of more helpful in this regard.
Thanks in advance.
Rane
Rane
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Perhaps you're after a profiler. MSVC 6 comes with one so I assume the newer ones also do. There are also third partly ones like NuMega’s TrueCoverage.
Steve
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When using CDaoDatabase and CDaoRecordset class.
How to make the database connection with user name and password ?
P.S. using VC6, Dao and Access 2000.
-- modified at 21:02 Friday 24th February, 2006
Is CDaoDatabase and CDaoRecordset
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Hi,
CDaoDatabase and CDaoRecordset is good choice.
In the connection string specify the username and the password.
For more information check this link
DAO[^]
Bye,
Cool Ju 
Dream Ur Destiny
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