Converting everything to and from wxString
This question seems common so I thought I'd write an article. Note that sometimes there may be more than one possible solutions, so don't forget to check the docs.
Note that it is recommended to use wxString as much as possible. Do no use char* or std::string unless you use a third-party library requires it.
Literals
A literal is a string written in code with "quotes around it". A char* is not a literal, and a wxString or a std::string neither. Unicode builds (prior to wxWidgets 3) require you to use one of these macros:
_("text that can be translated")
wxT("text that can't be translated")
_T("same as wxT")
char* c = "sometext";
wxT(c) // WRONG, not a literal
char* to wxString
char* chars = "Hello world";
wxString mystring(chars, wxConvUTF8);
wxString to char*
wxString mystring(wxT("HelloWorld"));
const char* cstring = mystring.mb_str();
int to wxString
wxString mystring = wxString::Format(wxT("%i"),myint);
or
wxString mystring;
mystring << myint;
float to wxString
wxString mystring = wxString::Format(wxT("%f"), myfloat);
or
wxString mystring;
mystring << myfloat;
wxString to integer number
wxString number(wxT("145"));
long value;
if(!s.ToLong(&value)); // error!
wxString to floating-point number
wxString number(wxT("3.14159"));
double value;
if(!s.ToDouble(&value)); // error!
std::string to wxString
std::string stlstring = "Hello world";
wxString mystring(stlstring.c_str(), wxConvUTF8);
wxString to std::string
wxString mystring(wxT("HelloWorld"));
std::string stlstring = std::string(mystring.mb_str());