C + + Builder string conversions (RPM)

Source: http://www.cnblogs.com/zhcncn/archive/2013/05/20/3089084.html

1. char*->string

(1) Direct conversion

char* nodename;string
String Temp2 (nodename);

2. wchar_t*->wstring

(1) Direct conversion

wchar_t* nodename;
Wstring Temp2 (nodename); 

3. string->char*

wstring->char*

Method One:

(1) Convert wstring.c_str () to wchar_t*

Method Two:

(1) Convert string.c_str (), Wstring.c_str () to Ansistring (http://blog.csdn.net/bannico/article/details/7577728),

(2) Convert ansistring.c_str () to char*

method One: string temp; Const Char* nodename = temp.c_str (); method two:struct  ipaddress{    std::wstring hostname;    Std::vector<std::wstring>= (*= dns.hostname.c_str (); char * HN = Stra.c_str ();

But it is said to be very unreliable (http://bbs.csdn.net/topics/30479944), the Safe Way is:

Method Three: String str="123456";  int len=str. Length (); Char *cp=char[len+1]; Strpcopy (CP, str);         

4. wstring->wchar_t*

string->w_char* (see 5)

Method One:

(1) Convert wstring.c_str () to wchar_t*

Method two. One:

(1) Convert wstring.c_str () to UnicodeString

(2) Convert unicodestring.c_str () to wchar_t*

Method Two. Two:

(1) Convert wstring.c_str () to Ansistring

(2) Convert ansistring.c_str () to wchar_t* using the Ansitounicode method

method One: wstring temp;wchar_t*NodeName =temp.c_str (); method two. One:structipaddress{std::wstring hostname; Std::vector<std::wstring>IPs;}; Scripting::ipaddress DNS= (*Ppreloaddns) [i]; UnicodeString Stra=dns.hostname.c_str ();//char * hn = STRA.C_STR ();wchar_t *HN =stra.c_str (); method two. Two:structipaddress{std::wstring hostname; Std::vector<std::wstring>IPs;}; Scripting::ipaddress DNS= (*Ppreloaddns) [i]; Ansistring Stra=dns.hostname.c_str ();//char * hn = STRA.C_STR ();wchar_t *HN = Ansitounicode (Stra.c_str ());

5. char*->unicodestring->wstring, wchar_t*

(1) Convert char* to UnicodeString

(2) Convert unicodestring.c_str () to Wstring, wchar_t*

std::wstring Addr (temp.c_str ()); wchar_t* addr2 = Temp.c_str (); Log_debug (_t ("Set Connection IP:") << addr); Con->setip (addr);  

6. Wchar_t*->ansistring->string, char*

(1) Convert wchar_t* to Ansistring

(2) Convert Ansistring.c_str () to String, char*

wchar_t* str = WSTRING.C_STR (); Ansistring temp (str); Inet_ntoa returns char*

Std::string addr (Temp.c_str ()); char* ADDR2 = Temp.c_str (); Log_debug (_t ("Set Connection IP:") << addr); Con->setip (addr);

The following method of string,wstring mutual transfer is wrong. The ANSI character may get the correct result, but if the passed in parameter is a "Chinese" string, the correct result will not be obtained.

7. String->wstring

static wstring str2wstr (string  str) {    if0)          return L"";    Std::wstring wstr;    Wstr.assign (Str.begin (), Str.end ());     return wstr;}

8. wstring->string

Static string wstr2str (wstring wstr) {    if0)        return"";    std::string  str;    Str.assign (Wstr.begin (), Wstr.end ());     return str;}

The correct approach is to use MultiByteToWideChar and WideCharToMultiByte:

9. string->wstring

Std::wstring stringtowstring (ConstSTD::string&str) {LPCSTR pszsrc=Str.c_str (); intNlen = MultiByteToWideChar (CP_ACP,0, PSZSRC,-1Null0); if(Nlen = =0)         returnStd::wstring (L""); wchar_t* PWSZDST =NewWchar_t[nlen]; if(!pwszdst)returnStd::wstring (L""); MultiByteToWideChar (CP_ACP,0, PSZSRC,-1, PWSZDST, Nlen);    Std::wstring wstr (PWSZDST);    Delete[] PWSZDST; PWSZDST=NULL; returnwstr;}

Ten. Wstring->string

STD::stringWstringtostring (Conststd::wstring&wstr) {LPCWSTR Pwszsrc=Wstr.c_str (); intNlen = WideCharToMultiByte (CP_ACP,0, PWSZSRC,-1Null0, NULL, NULL); if(Nlen = =0)         returnSTD::string(""); Char* PSZDST =New Char[Nlen]; if(!pszdst)returnSTD::string(""); WideCharToMultiByte (CP_ACP,0, PWSZSRC,-1, PSZDST, Nlen, NULL, and NULL); STD::stringstr (PSZDST);    Delete[] PSZDST; PSZDST=NULL; returnstr;}

Test code:

int_tmain (intARGC, _tchar*argv[]) {std::stringstr ="English"; Std::wstring Wstr= L"English"; STD::stringSTR1 =""; Std::wstring WSTR1= L""; LPCSTR PSRC="English"; LPCWSTR PWZSRC= L"English";    Stringtowstring (str);    Wstringtostring (WSTR);    Stringtowstring (STR1);    Wstringtostring (WSTR1);    Stringtowstring (PSRC);    Wstringtostring (PWZSRC); return 0;}

C + + Builder string conversions (RPM)