Conversion of wide character cstring and ANSI character const char * in Unicode

If you write a program in the Unicode environment today and convert the cstring to the const char * type, an error is returned: "cannot convert parameter 1 from 'wchar _ T * 'to 'const char *'". After a long search, we finally found three solutions:

 

First: The following method can be used in the com environment,

Cstring strsql;

Strsql. Format (_ T ('insert into class (name) values ('% s ')'),

M_strname.getbuffer (m_strname.getlength ()));

Char * pchsql = _ com_util: convertbstrtostring (strsql. getbuffer (strsql. getlength ()));

 

Second:Use the conversion function provided by the operating system,

 

 

 

Int nsize = widechartomultibyte (cp_acp,

Null,

Strsql. getbuffer (strsql. getlength ()),

-1,

Null,

0,

Null,

False );

Char * pchstr = new char [nsize];

Widechartomultibyte (cp_acp,

Null,

Strsql. getbuffer (strsql. getlength ()),

-1,

Pchstr,

Nsize,

Null,

False );

Delete pchstr;

 

 

Third: Use the conversion function provided by the C ++ Library:

# Include <stdlib. h>

......

Char pchsql [128] = {0 };

Wcstombs (pchsql, strsql, strsql. getlength ());