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Re: VC++ MFC questions henry00115-Jun-04 5:51 henry001 15-Jun-04 5:51  Thanks Geii power I wait for your reply when you are availiable. Thanks again Re: VC++ MFC questions toxcct15-Jun-04 5:52 toxcct 15-Jun-04 5:52  wow, GEII is the studies i am currently on... it's not me call me toxcct, i'll be fine for me TOXCCT >>> GEII power Re: VC++ MFC questions henry00115-Jun-04 5:56 henry001 15-Jun-04 5:56  Sorry, toxcct;P I will wait How to overload [] and = for bit assignment ICantChangeMyAcct14-Jun-04 15:48 ICantChangeMyAcct 14-Jun-04 15:48  I have the following class: template<typename FLAGTYPE> // may be BYTE, WORD, ULONG... class Flags { public: /** The boolean indexing operator returns true if the indexed flag bit is a one. */ bool operator[] (long ix) const { assert((long)ix >= 0 && (long)ix < 8*sizeof(FLAGTYPE)); return ((m_flags & (1<<ix)) != 0); } // ... protected: FLAGTYPE m_flags; }; The bool operator[] makes it possible to write: Flags<ULONG> f1 = 10; bool b = f1[3]; // assigns bit 3 of f1, i.e. f1 & 0x08, to b How do I define indexing and assignment operators that *set* bit 'ix' to a boolean value, so that I can write: f1[3] = true; Re: How to overload [] and = for bit assignment Michael Dunn14-Jun-04 20:28 Michael Dunn 14-Jun-04 20:28  You can't do that directly because the return value of a function can't be a bitfield. You would need to have operator[] return some object (probably a helper class) that has access to the members of Flags<> variable and an operator= that takes a bool parameter. That operator= would twiddle the right bit. --Mike-- Personal stuff:: Ericahist | Homepage Shareware stuff:: 1ClickPicGrabber | RightClick-Encrypt CP stuff:: CP SearchBar v2.0.2 | C++ Forum FAQ ---- If my rhyme was a drug, I'd sell it by the gram. Can I use Shell Extentions? ngocdq14-Jun-04 15:16 ngocdq 14-Jun-04 15:16  - I Want to detect a file which have received from other Computer on LAN. But I don't know way to approach. --> What's should i do?? --> Can I use Shell Extentions?? thanks Re: Can I use Shell Extentions? Iain Clarke, Warrior Programmer14-Jun-04 23:44 Iain Clarke, Warrior Programmer 14-Jun-04 23:44  *How* are you receiving it? If you've fetched it from the other computer, then look at the application fetching the file. If it is out of your control, (ie. you have a shared directory, and the other PC pushes the file), then you may be able to use the FindFirstChangeNotification API function. Iain. C++ question. WREY14-Jun-04 14:37 WREY 14-Jun-04 14:37  I created a structure inside a function definition (which means that the structure will be destroyed when I leave that function scope). While I'm inside that function however, I would like to activate another function (let's call it 'DoSomethingWithStruct') to handle certain activities on that newly created structure. In the class definition, I am able to get away declaring 'DoSomethingWithStruct' by using a 'void*' as the parameter to pass data between one function and the other. My problem is, "How do I cast the 'void*' back to the structure when I'm inside 'DoSomethingWithStruct'? (Here's some code.) class MyClass { ... void DoSomethingWithStruct(void* pMyStructure); }; =============================== void MyClass::FirstFn() { struct MyStruct {...}; ... DoSomethingWithStruct(pMyStruct); ... }; ================================ void MyClass::DoSomethingWithStruct(void* pMyStructure) { // Here is where I need to cast 'pMyStructure' back from a 'void', to a 'MyStruct' type. } ================================ I DO NOT want to declare 'MyStruct' as global. Thanks for any insight. William Fortes in fide et opere! Re: C++ question. palbano14-Jun-04 15:18 palbano 14-Jun-04 15:18  This would be better class MyClass { ... void DoSomethingWithStruct(MyStruct* pMyStructure); }; Re: C++ question. WREY14-Jun-04 18:02 WREY 14-Jun-04 18:02  Thanks for replying. 'MyClass' does not know of 'MyStruct' as a type, hence the reason I used 'void'. William Fortes in fide et opere! Re: C++ question. Indrawati14-Jun-04 16:37 Indrawati 14-Jun-04 16:37  Maybe you can just define the struct inside the class declaration instead of inside the function definition? You can make the struct private, so only members of the class can access it. Re: C++ question. WREY14-Jun-04 18:07 WREY 14-Jun-04 18:07  Thanks for replying. Your answer would presume that I own the class. (My error for referring to the class as 'MyClass'.) William Fortes in fide et opere! Re: C++ question. Indrawati14-Jun-04 18:46 Indrawati 14-Jun-04 18:46  Hi If you don't own the class, how can you change DoSomethingWithStruct() function definition, since it's a MyClass member? However, if DoSomethingWithStruct() is not member of MyClass, I don't know of any way (besides making a global structure) to make it aware of the struct. Sorry. Re: C++ question. WREY14-Jun-04 23:39 WREY 14-Jun-04 23:39  The point you make is a very good point, and the only answer I can give is that I've become a victim of my own cleverness. 'DoSomethingWithStruct' is a function I recognized I could use, and which I did, except I now find myself limited in what I could use it for. There are a couple other ways I could go (inheritance being one), but I would like to first explore if a simpler solution might still be available (even if it means applying additional creativity). Thanks for your replies anyway, I appreciate them. William Fortes in fide et opere! Re: C++ question. Michael Dunn14-Jun-04 20:31 Michael Dunn 14-Jun-04 20:31  The definition of the MyStruct type is local to MyClass::FirstFn() and it's not visible in MyClass::DoSomethingWithStruct(). No way around it, them's the rules of the language. You'll need to move the definition of the type into MyClass (type definitions can be nested). --Mike-- Personal stuff:: Ericahist | Homepage Shareware stuff:: 1ClickPicGrabber | RightClick-Encrypt CP stuff:: CP SearchBar v2.0.2 | C++ Forum FAQ ---- If my rhyme was a drug, I'd sell it by the gram. Re: C++ question. WREY14-Jun-04 23:50 WREY 14-Jun-04 23:50  Thanks for replying. I know what you're saying, but I've seen it too many times, when the doors seemed to be closed, there's a book somewhere holding a secret of one of the masters offering something the person didn't know about. The easiest thing here is for me to say, "Yes, I agree with you," and go the way of tradition (which is NOT always in keeping with what the person wants to achieve). I don't believe I've reached either that bridge, or the end of my line. Appreciate your response however. William Fortes in fide et opere! Re: C++ question. toxcct15-Jun-04 1:13 toxcct 15-Jun-04 1:13  ok, lets see. you pass a struct to your function, but the définition of your struct is not know into the function using it. well, you can do the manipulation by hand, but you (the writer of the function) must know the types of the members. this way, you could do some pointing... but if one day you change the type of one member in the struct, the function won"t be usable anymore... TOXCCT >>> GEII power Re: C++ question. WREY15-Jun-04 3:16 WREY 15-Jun-04 3:16  Thanks for replying. There's a lot of permutations to the things you're saying, but don't forget I can overload a function and apply my own set of parameters to it, so long as I make sure I can identify with at least one of the functions already declared in the class. That was one of the things that attracted me to the function with the 'void*' parameter (because it was already declared and I could use its 'void*' to transfer the struct data to it, and do my work where it's defined). Considering the amount of effort I might have to invest in order to make this creative idea of mine work, even if I were to succeed, in the end the poor person coming behind me might become lost (most likely would become lost) in the convolution behind the cleverness. That said, I am beginning to feel maybe I should just stick to something simpler; ESPECIALLY if it works!! William Fortes in fide et opere! Re: C++ question. toxcct15-Jun-04 3:24 toxcct 15-Jun-04 3:24  TOXCCT >>> GEII power Re: C++ question. toxcct14-Jun-04 22:15 toxcct 14-Jun-04 22:15  WREY wrote: I DO NOT want to declare 'MyStruct' as global just curious but, WHY ??? TOXCCT >>> GEII power Re: C++ question. bikram singh15-Jun-04 6:50 bikram singh 15-Jun-04 6:50  To preserve the "principle of encapsulation". Bikram Singh Re: C++ question. toxcct15-Jun-04 8:28 toxcct 15-Jun-04 8:28  but we never declare types into a function you answer, you answer, but do you try to understand the subject ? TOXCCT >>> GEII power Re: C++ question. bikram singh15-Jun-04 10:51 bikram singh 15-Jun-04 10:51  first, never say never! i admit i did not read the the thread completely, mu fault. but, it is possible to declare a struct inside of a function. sure, the uses may be limited, but it can be useful sometimes. one case i can think of is a simple log file which uses the struct as a "record". Sure, the "log reader" would need access to this struct too, which is why it's silly to have the struct inside the function. But it can have uses. Not that I can think of any at the moment! Bikram Singh About &#8216;HIWORD&#8217; macro myfapb14-Jun-04 14:10 myfapb 14-Jun-04 14:10  I apply ‘HIWORD’ macro to get the high byte from a WPARAM value, HOW can I get a negative value? For example: The value is –120,but what I get is 65416. Thank you!!! Re: About &#8216;HIWORD&#8217; macro palbano14-Jun-04 17:07 palbano 14-Jun-04 17:07  You want to find some material for C/C++ that discusses signed and unsigned types. Maybe you can look at cplusplus.com -pete

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