Como: Converter entre vários tipos de string
Este tópico demonstra como converter vários tipos de seqüência de caracteres do Visual C++ em outras strings.Os tipos de cadeias de caracteres que estão cobertos incluem char *, wchar_t*, _bstr_t, CComBSTR, CString, basic_string, and System.String. Em todos os casos, é feita uma cópia da seqüência de caracteres quando convertido para o novo tipo.Qualquer alteração feita para a nova seqüência não afetará a seqüência de caracteres original e vice-versa.
Exemplo
Descrição
Este exemplo demonstra como converter de um char * para outros tipos de seqüência de caracteres listados acima.
Código
// convert_from_char.cpp
// compile with: /clr /link comsuppw.lib
#include <iostream>
#include <stdlib.h>
#include <string>
#include "atlbase.h"
#include "atlstr.h"
#include "comutil.h"
using namespace std;
using namespace System;
int main()
{
char *orig = "Hello, World!";
cout << orig << " (char *)" << endl;
// Convert to a wchar_t*
size_t origsize = strlen(orig) + 1;
const size_t newsize = 100;
size_t convertedChars = 0;
wchar_t wcstring[newsize];
mbstowcs_s(&convertedChars, wcstring, origsize, orig, _TRUNCATE);
wcscat_s(wcstring, L" (wchar_t *)");
wcout << wcstring << endl;
// Convert to a _bstr_t
_bstr_t bstrt(orig);
bstrt += " (_bstr_t)";
cout << bstrt << endl;
// Convert to a CComBSTR
CComBSTR ccombstr(orig);
if (ccombstr.Append(L" (CComBSTR)") == S_OK)
{
CW2A printstr(ccombstr);
cout << printstr << endl;
}
// Convert to a CString
CString cstring(orig);
cstring += " (CString)";
cout << cstring << endl;
// Convert to a basic_string
string basicstring(orig);
basicstring += " (basic_string)";
cout << basicstring << endl;
// Convert to a System::String
String ^systemstring = gcnew String(orig);
systemstring += " (System::String)";
Console::WriteLine("{0}", systemstring);
delete systemstring;
}
Saída
Hello, World! (char *)
Hello, World! (wchar_t *)
Hello, World! (_bstr_t)
Hello, World! (CComBSTR)
Hello, World! (CString)
Hello, World! (basic_string)
Hello, World! (System::String)
Exemplo
Descrição
Este exemplo demonstra como converter de um wchar_t * para outros tipos de seqüência de caracteres listados acima.
Código
// convert_from_wchar_t.cpp
// compile with: /clr /link comsuppw.lib
#include <iostream>
#include <stdlib.h>
#include <string>
#include "atlbase.h"
#include "atlstr.h"
#include "comutil.h"
using namespace std;
using namespace System;
int main()
{
wchar_t *orig = L"Hello, World!";
wcout << orig << L" (wchar_t *)" << endl;
// Convert to a char*
size_t origsize = wcslen(orig) + 1;
const size_t newsize = 100;
size_t convertedChars = 0;
char nstring[newsize];
wcstombs_s(&convertedChars, nstring, origsize, orig, _TRUNCATE);
strcat_s(nstring, " (char *)");
cout << nstring << endl;
// Convert to a _bstr_t
_bstr_t bstrt(orig);
bstrt += " (_bstr_t)";
cout << bstrt << endl;
// Convert to a CComBSTR
CComBSTR ccombstr(orig);
if (ccombstr.Append(L" (CComBSTR)") == S_OK)
{
CW2A printstr(ccombstr);
cout << printstr << endl;
}
// Convert to a CString
CString cstring(orig);
cstring += " (CString)";
cout << cstring << endl;
// Convert to a basic_string
wstring basicstring(orig);
basicstring += L" (basic_string)";
wcout << basicstring << endl;
// Convert to a System::String
String ^systemstring = gcnew String(orig);
systemstring += " (System::String)";
Console::WriteLine("{0}", systemstring);
delete systemstring;
}
Saída
Hello, World! (wchar_t *)
Hello, World! (char *)
Hello, World! (_bstr_t)
Hello, World! (CComBSTR)
Hello, World! (CString)
Hello, World! (basic_string)
Hello, World! (System::String)
Exemplo
Descrição
Este exemplo demonstra como converter de um _bstr_t para outros tipos de seqüência de caracteres listados acima.
Código
// convert_from_bstr_t.cpp
// compile with: /clr /link comsuppw.lib
#include <iostream>
#include <stdlib.h>
#include <string>
#include "atlbase.h"
#include "atlstr.h"
#include "comutil.h"
using namespace std;
using namespace System;
int main()
{
_bstr_t orig("Hello, World!");
wcout << orig << " (_bstr_t)" << endl;
// Convert to a char*
const size_t newsize = 100;
char nstring[newsize];
strcpy_s(nstring, (char *)orig);
strcat_s(nstring, " (char *)");
cout << nstring << endl;
// Convert to a wchar_t*
wchar_t wcstring[newsize];
wcscpy_s(wcstring, (wchar_t *)orig);
wcscat_s(wcstring, L" (wchar_t *)");
wcout << wcstring << endl;
// Convert to a CComBSTR
CComBSTR ccombstr((char *)orig);
if (ccombstr.Append(L" (CComBSTR)") == S_OK)
{
CW2A printstr(ccombstr);
cout << printstr << endl;
}
// Convert to a CString
CString cstring((char *)orig);
cstring += " (CString)";
cout << cstring << endl;
// Convert to a basic_string
string basicstring((char *)orig);
basicstring += " (basic_string)";
cout << basicstring << endl;
// Convert to a System::String
String ^systemstring = gcnew String((char *)orig);
systemstring += " (System::String)";
Console::WriteLine("{0}", systemstring);
delete systemstring;
}
Saída
Hello, World! (_bstr_t)
Hello, World! (char *)
Hello, World! (wchar_t *)
Hello, World! (CComBSTR)
Hello, World! (CString)
Hello, World! (basic_string)
Hello, World! (System::String)
Exemplo
Descrição
Este exemplo demonstra como converter de um CComBSTR para outros tipos de seqüência de caracteres listados acima.
Código
// convert_from_ccombstr.cpp
// compile with: /clr /link comsuppw.lib
#include <iostream>
#include <stdlib.h>
#include <string>
#include "atlbase.h"
#include "atlstr.h"
#include "comutil.h"
#include "vcclr.h"
using namespace std;
using namespace System;
using namespace System::Runtime::InteropServices;
int main()
{
CComBSTR orig("Hello, World!");
CW2A printstr(orig);
cout << printstr << " (CComBSTR)" << endl;
// Convert to a char*
const size_t newsize = 100;
char nstring[newsize];
CW2A tmpstr1(orig);
strcpy_s(nstring, tmpstr1);
strcat_s(nstring, " (char *)");
cout << nstring << endl;
// Convert to a wchar_t*
wchar_t wcstring[newsize];
wcscpy_s(wcstring, orig);
wcscat_s(wcstring, L" (wchar_t *)");
wcout << wcstring << endl;
// Convert to a _bstr_t
_bstr_t bstrt(orig);
bstrt += " (_bstr_t)";
cout << bstrt << endl;
// Convert to a CString
CString cstring(orig);
cstring += " (CString)";
cout << cstring << endl;
// Convert to a basic_string
wstring basicstring(orig);
basicstring += L" (basic_string)";
wcout << basicstring << endl;
// Convert to a System::String
String ^systemstring = gcnew String(orig);
systemstring += " (System::String)";
Console::WriteLine("{0}", systemstring);
delete systemstring;
}
Saída
Hello, World! (CComBSTR)
Hello, World! (char *)
Hello, World! (wchar_t *)
Hello, World! (_bstr_t)
Hello, World! (CString)
Hello, World! (basic_string)
Hello, World! (System::String)
Exemplo
Descrição
Este exemplo demonstra como converter de um CString para outros tipos de seqüência de caracteres listados acima.
Código
// convert_from_cstring.cpp
// compile with: /clr /link comsuppw.lib
#include <iostream>
#include <stdlib.h>
#include <string>
#include "atlbase.h"
#include "atlstr.h"
#include "comutil.h"
using namespace std;
using namespace System;
int main()
{
CString orig("Hello, World!");
wcout << orig << " (CString)" << endl;
// Convert to a char*
const size_t newsize = 100;
char nstring[newsize];
strcpy_s(nstring, orig);
strcat_s(nstring, " (char *)");
cout << nstring << endl;
// Convert to a wchar_t*
// You must first convert to a char * for this to work.
size_t origsize = strlen(orig) + 1;
size_t convertedChars = 0;
wchar_t wcstring[newsize];
mbstowcs_s(&convertedChars, wcstring, origsize, orig, _TRUNCATE);
wcscat_s(wcstring, L" (wchar_t *)");
wcout << wcstring << endl;
// Convert to a _bstr_t
_bstr_t bstrt(orig);
bstrt += " (_bstr_t)";
cout << bstrt << endl;
// Convert to a CComBSTR
CComBSTR ccombstr(orig);
if (ccombstr.Append(L" (CComBSTR)") == S_OK)
{
CW2A printstr(ccombstr);
cout << printstr << endl;
}
// Convert to a basic_string
string basicstring(orig);
basicstring += " (basic_string)";
cout << basicstring << endl;
// Convert to a System::String
String ^systemstring = gcnew String(orig);
systemstring += " (System::String)";
Console::WriteLine("{0}", systemstring);
delete systemstring;
}
Saída
Hello, World! (CString)
Hello, World! (char *)
Hello, World! (wchar_t *)
Hello, World! (_bstr_t)
Hello, World! (CComBSTR)
Hello, World! (basic_string)
Hello, World! (System::String)
Exemplo
Descrição
Este exemplo demonstra como converter de um basic_string para outros tipos de seqüência de caracteres listados acima.
Código
// convert_from_basic_string.cpp
// compile with: /clr /link comsuppw.lib
#include <iostream>
#include <stdlib.h>
#include <string>
#include "atlbase.h"
#include "atlstr.h"
#include "comutil.h"
using namespace std;
using namespace System;
int main()
{
string orig("Hello, World!");
cout << orig << " (basic_string)" << endl;
// Convert to a char*
const size_t newsize = 100;
char nstring[newsize];
strcpy_s(nstring, orig.c_str());
strcat_s(nstring, " (char *)");
cout << nstring << endl;
// Convert to a wchar_t*
// You must first convert to a char * for this to work.
size_t origsize = strlen(orig.c_str()) + 1;
size_t convertedChars = 0;
wchar_t wcstring[newsize];
mbstowcs_s(&convertedChars, wcstring, origsize, orig.c_str(), _TRUNCATE);
wcscat_s(wcstring, L" (wchar_t *)");
wcout << wcstring << endl;
// Convert to a _bstr_t
_bstr_t bstrt(orig.c_str());
bstrt += " (_bstr_t)";
cout << bstrt << endl;
// Convert to a CComBSTR
CComBSTR ccombstr(orig.c_str());
if (ccombstr.Append(L" (CComBSTR)") == S_OK)
{
CW2A printstr(ccombstr);
cout << printstr << endl;
}
// Convert to a CString
CString cstring(orig.c_str());
cstring += " (CString)";
cout << cstring << endl;
// Convert to a System::String
String ^systemstring = gcnew String(orig.c_str());
systemstring += " (System::String)";
Console::WriteLine("{0}", systemstring);
delete systemstring;
}
Saída
Hello, World! (basic_string)
Hello, World! (char *)
Hello, World! (wchar_t *)
Hello, World! (_bstr_t)
Hello, World! (CComBSTR)
Hello, World! (CString)
Hello, World! (System::String)
Exemplo
Descrição
Este exemplo demonstra como converter de um System.String para outros tipos de seqüência de caracteres listados acima.
Código
// convert_from_system_string.cpp
// compile with: /clr /link comsuppw.lib
#include <iostream>
#include <stdlib.h>
#include <string>
#include "atlbase.h"
#include "atlstr.h"
#include "comutil.h"
#include "vcclr.h"
using namespace std;
using namespace System;
using namespace System::Runtime::InteropServices;
int main()
{
String ^orig = gcnew String("Hello, World!");
Console::WriteLine("{0} (System::String)", orig);
pin_ptr<const wchar_t> wch = PtrToStringChars(orig);
// Convert to a char*
size_t origsize = wcslen(wch) + 1;
const size_t newsize = 100;
size_t convertedChars = 0;
char nstring[newsize];
wcstombs_s(&convertedChars, nstring, origsize, wch, _TRUNCATE);
strcat_s(nstring, " (char *)");
cout << nstring << endl;
// Convert to a wchar_t*
wchar_t wcstring[newsize];
wcscpy_s(wcstring, wch);
wcscat_s(wcstring, L" (wchar_t *)");
wcout << wcstring << endl;
// Convert to a _bstr_t
_bstr_t bstrt(wch);
bstrt += " (_bstr_t)";
cout << bstrt << endl;
// Convert to a CComBSTR
CComBSTR ccombstr(wch);
if (ccombstr.Append(L" (CComBSTR)") == S_OK)
{
CW2A printstr(ccombstr);
cout << printstr << endl;
}
// Convert to a CString
CString cstring(wch);
cstring += " (CString)";
cout << cstring << endl;
// Convert to a basic_string
wstring basicstring(wch);
basicstring += L" (basic_string)";
wcout << basicstring << endl;
delete orig;
}
Saída
Hello, World! (System::String)
Hello, World! (char *)
Hello, World! (wchar_t *)
Hello, World! (_bstr_t)
Hello, World! (CComBSTR)
Hello, World! (CString)
Hello, World! (basic_string)
Consulte também
Tarefas
Como: Converter string padrão sistema::String
Como: Converter sistema::String em cadeia de caracteres padrão
Como: Converter sistema::String wchar_t * ou char *
Conceitos
ATL e MFC macros de conversão de cadeia de caracteres
CString operações relacionadas a estilo C seqüências de caracteres