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Re: How do i make a Radio Button set at runtime? valikac1-Oct-02 5:45 valikac 1-Oct-02 5:45  Are you using Win32 API or MFC? One solution is SetCheck(). Kuphryn Re: How do i make a Radio Button set at runtime? Anonymous1-Oct-02 5:52 Anonymous 1-Oct-02 5:52  I'm using Win32 API Re: How do i make a Radio Button set at runtime? valikac1-Oct-02 10:31 valikac 1-Oct-02 10:31  Here is one solution. // Enable a dialog control EnableWindow(GetDlgItem(hDlg, ID_EDIT), TRUE) // Disable a dialog control EnableWindow(GetDlgItem(hDlg, ID_EDIT), FALSE) Kuphryn strlen and char* ns1-Oct-02 4:49 ns 1-Oct-02 4:49  I have a char* a ="a sentence" . I need to copy this into another char* b , after allocating enough memory to b. I am very unsure about how to get the length of a so I can do char *b = new char[a_length+1]; If I use strlen, how exactly do I code this? a_length = strlen(*a); or a_length = strlen(a);</ Appreciate your help, ns Re: strlen and char* Nish Nishant1-Oct-02 4:56 Nish Nishant 1-Oct-02 4:56  ns wrote: a_length = strlen(a); This is correct Nish Author of the romantic comedy Summer Love and Some more Cricket [New Win] Review by Shog9 Click here for review[NW] Re: strlen and char* User 66581-Oct-02 5:14 User 6658 1-Oct-02 5:14  char *a="a sentence\0"; char *b = new char[strlen(a)]; make sure your string "a" is null-terminated. I don't know whether this is necessary, though modified 12-Sep-18 21:01pm. Re: strlen and char* ns1-Oct-02 5:17 ns 1-Oct-02 5:17  That sounds good too. Though I am wondering if the way you have definred the string it now has two NULLS at the end....? Appreciate your help, ns Re: strlen and char* Michael Dunn1-Oct-02 5:21 Michael Dunn 1-Oct-02 5:21  Gregor's code is wrong, Nish already gave you the correct answer. Use strlen() to count the characters, then add 1 for the terminating 0 character. --Mike-- Just released - 1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click! My really out-of-date homepage Sonork-100.19012 Acid_Helm Re: strlen and char* Michael Dunn1-Oct-02 5:18 Michael Dunn 1-Oct-02 5:18  What? No one writes strings like that, don't confuse him. --Mike-- Just released - 1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click! My really out-of-date homepage Sonork-100.19012 Acid_Helm Re: strlen and char* User 66581-Oct-02 5:23 User 6658 1-Oct-02 5:23  But the string needs to be null-terminated, or am I wrong? He could also write char a[] = "a sentence"; Now you have confused me totally modified 12-Sep-18 21:01pm. Re: strlen and char* jmkhael1-Oct-02 5:30 jmkhael 1-Oct-02 5:30  just by doing char* pcChar = ""; u have a null terminated string, u usualy dont add \0 to the string but in special cases, like a filter for a CFileDialog for instance Papa while (TRUE) Papa.WillLove ( Bebe ) ; Re: strlen and char* User 66581-Oct-02 5:38 User 6658 1-Oct-02 5:38  Oh my god, it's really awkward I didn't know that Sorry Michael, thanks Papa regards btw. nice signature you have there, is Bebe your wife? modified 12-Sep-18 21:01pm. Re: strlen and char* jmkhael1-Oct-02 5:42 jmkhael 1-Oct-02 5:42  Glad i could help no not my wife Papa while (TRUE) Papa.WillLove ( Bebe ) ; Re: strlen and char* Daniel Turini1-Oct-02 6:00 Daniel Turini 1-Oct-02 6:00  Gregor S. wrote: char *a="a sentence\0"; You don't need the extra \0 Gregor S. wrote: char *b = new char[strlen(a)]; This is the wrong way. Allways alloc +1 byte for the \0 char *b = new char[strlen(a)+1]; "In an organization, each person rises to the level of his own incompetence." Peter's Principle strcpy and CString question ns1-Oct-02 4:34 ns 1-Oct-02 4:34  I need to convert a CString into a char*. If the CString is called fldName, then is the following allowed? char* fldName0 = new char [fldName.GetLength()+1]; strcpy(fldName0, fldName); The definition of strcpy has two char* as arguments, so I am wondering.... Appreciate your help, ns Re: strcpy and CString question Nish Nishant1-Oct-02 4:46 Nish Nishant 1-Oct-02 4:46  CString has an implicit LPCTSTR operator. So you can do this. char *abc = new char[s.GetLength()+1]; strcpy(abc,(LPTSTR)s);//cast LPCTSTR to LPTSTR Nish Author of the romantic comedy Summer Love and Some more Cricket [New Win] Review by Shog9 Click here for review[NW] Re: strcpy and CString question ns1-Oct-02 4:52 ns 1-Oct-02 4:52  Thank you. Appreciate your help, ns Re: strcpy and CString question Michael Dunn1-Oct-02 5:17 Michael Dunn 1-Oct-02 5:17  Nishant S wrote: (LPTSTR)s NO NO NO. Sorry, I get upset when I see people do that. That is totally wrong and a bad habit to get newbie programmers into. First off, the second strcpy() argument is a const char* (I'm avoiding the TCHAR typenames because ns obviously doesn't know them). There is no cast needed because CString has a const char* conversion operator that is called implicitly. Second, casting a CString to a char* breaks the CString interface -- you are using your knowledge of how a CString works internally, which you must not do to maintain OO encapsulation. The correct way to get a non-const pointer is GetBuffer(). --Mike-- Just released - 1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click! My really out-of-date homepage Sonork-100.19012 Acid_Helm Re: strcpy and CString question Jon Hulatt1-Oct-02 5:30 Jon Hulatt 1-Oct-02 5:30  Michael Dunn wrote: The correct way to get a non-const pointer is GetBuffer(). Yeah, but ns only wanted a const char *. To fiddle around with GetBuffer() is unnecessary here, why force CString to allocate new memory when he's only reading it? But, more to the point, the whole idea of "converting" the CString to char * is a bit fruitless. You can interchange CString operator char * and CString::GetBuffer entirely for read and write operations that need char *, and this will be quicker than what amounts to doing everything twice, not to mention obfuscates the code. Jon Signature space for rent. Apply by email to.... Re: strcpy and CString question Jon Hulatt1-Oct-02 5:35 Jon Hulatt 1-Oct-02 5:35  oops. i only part read your answer properly. ignore the bits that make no sense Signature space for rent. Apply by email to.... Re: strcpy and CString question Nitron1-Oct-02 5:31 Nitron 1-Oct-02 5:31  Michael Dunn wrote: NO NO NO. Sorry, I get upset when I see people do that. That is totally wrong and a bad habit to get newbie programmers into. First off, the second strcpy() argument is a const char* (I'm avoiding the TCHAR typenames because ns obviously doesn't know them). There is no cast needed because CString has a const char* conversion operator that is called implicitly. Second, casting a CString to a char* breaks the CString interface -- you are using your knowledge of how a CString works internally, which you must not do to maintain OO encapsulation. The correct way to get a non-const pointer is GetBuffer(). -- The more I learn, the more I realize how little I know Thanks Mike, I always learn something from your posts, even if they aren't my questions! Nitron _________________________________________-- message sent on 100% recycled electrons. Re: strcpy and CString question Nish Nishant1-Oct-02 5:38 Nish Nishant 1-Oct-02 5:38  Michael Dunn wrote: First off, the second strcpy() argument is a const char* Oops! When ns mentioned that strcpy takes two char*s I sorta got absent minded about it Michael Dunn wrote: Second, casting a CString to a char* breaks the CString interface Agreed! But here he only wanted a read-only char*. But I agree that it goes against OOP. Regards, Nish p.s. Never on sonork eh? No beer in LA? Author of the romantic comedy Summer Love and Some more Cricket [New Win] Review by Shog9 Click here for review[NW] Re: strcpy and CString question JT Anderson1-Oct-02 5:41 JT Anderson 1-Oct-02 5:41  In an attempt to clarify and emphasize Michael's response... The explicit and gratuitous cast than Nish suggests is very bad practice. The original poster's code was entirely correct. As Michael said, CString has a conversion operator to LPCTSTR (aka "const char *"). The second argument to strcpy is a const char *, not a char *, so the implicit conversion occurs and everybody's happy. The gratuitous cast that Nish suggested is unnecessary and could later hide errors introduced by subsequent changes to the code. NEVER USE EXPLICIT CASTS UNLESS YOU ABSOLUTELY MUST! I might add that the whole idea of allocating this buffer to a dumb pointer and then copying the string into it is quite questionable. We'd need more context to know whether or not there is any justification for it. Re: strcpy and CString question Nish Nishant1-Oct-02 5:54 Nish Nishant 1-Oct-02 5:54  JT Anderson wrote: explicit and gratuitous *Nish staggers on to the ground, first Mike's dagger had pierced his chest and now JT's sword had cut his body into two, and bleeds to death* But seriously thanks, I do have this bad habit. I have a lot of non-MFC code where I have a lot of functions that take char*s and when I reuse them from my MFC code I do make explicit casts from CString to char* (only when I am sure the char*s are read-only as far as the function is concerned, in which case I should actually have declared the arguments as const char* which I didn't do - another bad habit of mine) But it is a real nasty bad habit and I better get myself out of it Thanks fellas Nish Author of the romantic comedy Summer Love and Some more Cricket [New Win] Review by Shog9 Click here for review[NW] Re: strcpy and CString question Michael Dunn1-Oct-02 7:48 Michael Dunn 1-Oct-02 7:48  I think I should write an article "How to Convert CStrings Properly" David Wulff:BT::Me:casting CStrings --Mike-- Just released - 1ClickPicGrabber - Grab & organize pictures from your favorite web pages, with 1 click! My really out-of-date homepage Sonork-100.19012 Acid_Helm

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