Click here to Skip to main content
15,922,512 members
Please Sign up or sign in to vote.
2.00/5 (2 votes)
See more:
Hi,

I need to find the length of an LPCTSTR string in C++. I'm totally new to C++ and kind of lost. Can someone please help me out with it?

Thanks a lot.
Posted
Comments
Volynsky Alex 26-Apr-13 15:12pm    
Try to read the following post:
http://social.msdn.microsoft.com/Forums/en-US/Vsexpressvc/thread/016b8b40-1c56-4b6c-9e6b-86ccdf70321b/

Microsoft has a set of typedefs and macros that depend on the _UNICODE and _MBCS define. You can control the presence of these defines by tweaking the project settings in your Visual Studio Project. Normally you can write the source once and the compile it with many different text encoding settings if you use fancy type-names like LPCTSTR, the _TEXT() macro, and functions (sorry - macros) like _tcslen().
C++
LPCTSTR my_ptr = _TEXT("funny thing");
size_t len = _tcslen(my_ptr);

Depending on your project settings the above code may be preprocessed to:
C++
const char* my_ptr = "funny thing";
size_t len = strlen(my_ptr);

or
C++
const wchar_t* my_ptr = L"funny thing";
size_t len = wcslen(my_ptr);

or
whatever else...

What I recommend is supporting utf-16 only or utf-16 + utf-8 mixed and forget about fancy microsoft types and macros if you don't want to waste your time for nothing. Turn your project setting to unicode to ask the preprocessor to preprocess your windows system calls to the 'W' (widechar/utf16) version and handle strings/encoding yourself with utf encodings only (ansi is the past). Current windows versions have NT kernel for more than a decade and WinNT uses utf-16 internally so supporting for example ansi besides the widechar version of winapi functions makes no sense. What I ususually do is using utf8 internally in my program (this helps avoiding for example the 'L' prefix in case of strings and saves memory usage) and convert the strings to utf16 for windows only in case of system calls. With proper string classes you can store string in any (platform dependent) format hiding this under the interface, so you can write a string class that stores the string in utf16 for windows and utf8 for unix systems in the same program if string-using system calls are frequent... utf8 makes it easy to port your app to unix like systems while Microsoft macros just complicate things even if you target windows platform exclusively.
 
Share this answer
 
LPCTSTR is defined as either a const char* or const wchar_t*, depending on your project settings of Character Set (multi-byte or Unicode). There is Microsoft specific functions that is also defined depending on this setting and treats in the correct way: _tcslen.
C++
LPCTSTR pToMyString = _T("This is my string");
size_t len = _tcslen (pToMyString);
 
Share this answer
 
Comments
SajeeshCheviry 26-Apr-13 12:56pm    
Good answer
LPCTSTR is the alias in MFC for const char*. You can get the length of a string e.g. with the oldschool C-style function strlen.

C++
LPCTSTR s = "foobar";
std::cout << "Length of s is " << strlen(s);


Or since you are apparently working with MFC, you could as well instantiate a CString object by the LPCTSTR variable and get the length from the CString.

C++
LPCTSTR s = "foobar";
CString cs = s;
std::cout << "Length of s is " << cs.GetLength();


EDIT:
Just read that LPCTSTR (Long Pointer to a Const TCHAR STRing) could also be a const wchar_t* depending on the _UNICODE constant.
 
Share this answer
 
v2

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)



CodeProject, 20 Bay Street, 11th Floor Toronto, Ontario, Canada M5J 2N8 +1 (416) 849-8900