A valid method for converting cstring to const char *

In Visual Studio 200x, it is a little difficult to directly convert cstring to const char *. The following is a feasible solution:

// Obtain the directory path

Cstring mpath = DLG. getpathname ();

// Convert the directory path to an absolute path for cvloadimage to call

Int M = mpath. getlength ();
For (INT Index = 0; index <m; index ++)
{
If (mpath. getat (INDEX) = '\\')
{
Mpath. insert (index ,'\\');
Index ++;
}

}

// Convert the cstring to the lpctstr

Lpctstr P = mpath. getbuffer ();

/*

Convert the lpctstr to const char *. Due to Unicode problems1. Const char * in a non-Unicode Environment *2. In the Unicode environment
Const unsigned short *

In Case 2, you need to use the API FunctionWidechartomultibyte

Int widechartomultibyte (uint codePage, // code page DWORD dwflags, // performance and mapping flags lpcwstr lpwidecharstr, // wide-character string int cchwidechar, // Number of chars in string lpstr lpmultibytestr, // buffer for new string int cbmultibyte, // size of buffer lpcstr lpdefaultchar, // default for unmappable chars lpbool lpuseddefachar char // set when default char used );
 

*/

DWORD dwminsize;
Dwminsize = widechartomultibyte (cp_acp, null, P,-1, null, 0, null, false );
Char * PP = new char [dwminsize];
Widechartomultibyte (cp_oemcp, null, P,-1, PP, dwminsize, null, false );

// Read the image
Iplimage * IP1 = cvloadimage (PP,-1 );