c++ - Convert std::wstring to WCHAR* -


i have no idea how convert std::wstring wchar*

std::wstring wstrproctosearch; wchar * wpproctosearch = null;  std::wcin >> wstrproctosearch;  // input std::wstring // need convert wstring wchar*

does know how accomplish this?

if want convert std::wstring const wchar* (i.e. returned pointer gives read-only access string content), calling std::wstring::c_str() method fine:

std::wstring wstrproctosearch; std::wcin >> wstrproctosearch;  // input std::wstring  // convert const wchar* (read-only access) const wchar * wpszproctosearch = wstrproctosearch.c_str();

instead, if want modify std::wstring's content, things different. can use &wstr[0] (where wstr non-empty instance of std::wstring) access content of std::wstring (starting address of first characters, , noting characters stored contiguously in memory), must pay attention not overrun string's pre-allocated memory.

in general, if have std::wstring of length l, can access characters index 0 (l-1).
overwriting terminating '\0' (located @ index l) undefined behavior (in practice, it's ok on visual c++, @ least vc9/vs2008 , vc10/vs2010).

if string has not proper size (i.e. it's not big enough needs), can call std::wstring::resize() make room new characters (i.e. resizing internal std::wstring's buffer), , use &wstr[0] read-write std::wstring's content.


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