VC中BSTR、Char和CString类型的转换（太牛了）

1、char*转换成CString

char chArray[] = "This is a test";
char * p = "This is a test";

LPSTR p = "This is a test";

TCHAR * p = _T("This is a test");

LPTSTR p = _T("This is a test");
CString theString = chArray;
theString.format(_T("%s"), chArray);
theString = p;

2、CString转换成char*

CString theString( "This is a test" );
LPTSTR lpsz =(LPTSTR)(LPCTSTR)theString; 方法二，使用strcpy。例如：

CString theString( "This is a test" );
LPTSTR lpsz = new TCHAR[theString.GetLength()+1];_tcscpy(lpsz, theString);

CString s(_T("This is a test "));
LPTSTR p = s.GetBuffer();
// 在这里添加使用p的代码
if(p != NULL) *p = _T('/0');
s.ReleaseBuffer(); // 使用完后及时释放，以便能使用其它的CString成员函数

3、BSTR转换成char*

#include #pragma comment(lib, "comsupp.lib")
int _tmain(int argc, _TCHAR* argv[])
{
BSTR bstrText = ::SysAllocString(L"Test");
char* lpszText2 = _com_util::ConvertBSTRToString(bstrText);
SysFreeString(bstrText); // 用完释放
delete[] lpszText2;
return 0;
}

_bstr_t b = bstrText;
char* lpszText2 = b;

4、char*转换成BSTR

BSTR bstrText = ::SysAllocString(L"Test");
BSTR bstrText = ::SysAllocStringLen(L"Test",4);
BSTR bstrText = ::SysAllocStringByteLen("Test",4);

//COleVariant strVar("This is a test");
_variant_t strVar("This is a test");
BSTR bstrText = strVar.bstrVal;

BSTR bstrText = _bstr_t("This is a test");

BSTR bstrText = CComBSTR("This is a test"); 或
CComBSTR bstr("This is a test");
BSTR bstrText = bstr.m_str;

char* lpszText = "Test";
BSTR bstrText = _com_util::ConvertStringToBSTR(lpszText);

5、CString转换成BSTR

CString str("This is a test");
BSTR bstrText = str.AllocSysString();
…
SysFreeString(bstrText); // 用完释放

6、BSTR转换成CString

BSTR bstrText = ::SysAllocString(L"Test");
CStringA str;
str.Empty();
str = bstrText; 或

CStringA str(bstrText);

7、ANSI、Unicode和宽字符之间的转换

TCHAR tstr[] = _T("this is a test");
wchar_t wszStr[] = L"This is a test";

LPTSTR tstr= CA2TEX<16>("this is a test");
LPCTSTR tcstr= CA2CT("this is a test");
wchar_t wszStr[] = L"This is a test";
char* chstr = CW2A(wszStr);

结语

#include
using namespace std;
#include

{
CString strCString="ABC";
char strchar[256],*pstr;

pstr=(LPSTR)(LPCTSTR)strCString; //CString---->char*
strcpy(strchar,(LPSTR)(LPCTSTR)strCString); //CString---->char[]

_bstr_t strbstr=pstr; //char*---->_bstr_t
WCHAR *strWCHAR=strbstr; //b_str_t--->UNICODE

strbstr=strWCHAR;
pstr=strbstr; //UNICODE---->char*

strCString="10";
int istr=atoi((LPSTR)(LPCTSTR)strCString); //CString、char[]、char*------>int
strCString.Format("%d",istr); //int----->CString
sprintf(strchar,"%d",istr); //int----->char[]

pstr=new char[256]; //字符串申请空间
strcpy(pstr,"ABC"); //字符串赋值
delete []pstr; //字符串释放

string strstring="ABC";
pstr=(char*)strstring.c_str(); //string---->char*

strCString="2003-10-27 6:24:37"; //CString--->COleDateTime
COleVariant vtime(strCString);
vtime.ChangeType(VT_DATE);
COleDateTime time4=vtime;

COleDateTime time1(1977,4,16,2,2,2); //COleDataTime--->CTime
SYSTEMTIME systime;
VariantTimeToSystemTime(time1, &systime);
CTime tm(systime);

time_t time2=tm.GetTime(); //CTime--->time_t
COleDateTime time3(time2); //time_t--->COleDateTime

//判断字符串是否是某种类型
CString sValue("123.1");
COleVariant vValue(sValue);

BOOL bStrIsFloat = (SUCCEEDED(VariantChangeType(&vValue, &vValue, 0, VT_R8)) && sValue.Find('.') != -1);
if(bStrIsFloat)
{
AfxMessageBox("浮点");
}
}

HRESULT IWebBrowser2::put_StatusText( BSTR bstr );
// shows using the Win32 function
// to allocate memory for the string:
BSTR bstrStatus = ::SysAllocString( L"Some text" );
if (bstrStatus == NULL)
return E_OUTOFMEMORY;

pBrowser->put_StatusText( bstrStatus );
// Free the string:
::SysFreeString( bstrStatus );
//...

HRESULT IWebBrowser2::get_StatusText( BSTR FAR* pbstr );
//...
BSTR bstrStatus;
pBrowser->get_StatusText( &bstrStatus );

// shows using the Win32 function
// to freee the memory for the string:
::SysFreeString( bstrStatus );

// Example shows using MFC's
// CString::AllocSysString

//...
HRESULT CMyClass::get_StatusText( BSTR * pbstr )
{
try
{
//m_str is a CString in your class
*pbstr = m_str.AllocSysString( );
}
catch (...)
{
return E_OUTOFMEMORY;
}
// The client is now responsible for freeing pbstr.
return( S_OK );
}
//...

// 1.
_bstr_t strName = BATCHUNIT_CALC_NAME;
TEST_ASSERT (S_OK == machine->GetUnit(strName, &pUnit));

// 2.
CComBSTR cbstrName = BATCHUNIT_CALC_NAME;
TEST_ASSERT (S_OK == machine->GetUnit(cbstrName, &pUnit));

// 3.
TEST_ASSERT (S_OK == machine->GetUnit(_bstr_t(BATCHUNIT_CALC_NAME), &pUnit));

// 4.
CString csName = BATCHUNIT_CALC_NAME;
TEST_ASSERT (S_OK == machine->GetUnit(_bstr_t(csName), &pUnit));

// 1.
CComBSTR strRet21 = NULL;
machine->GetParameter(_bstr_t(L"WaitForEachApply"), &(strRet21.m_str));

// 2.
BSTR strRet20 = NULL;
machine->GetParameter(_bstr_t(L"WaitForEachApply"), &strRet20);
_bstr_t strUse(strRet20, false);

STDMETHODIMP BatchMachine::GetParameter(BSTR strName, BSTR *strValue)
{
AFX_MANAGE_STATE(AfxGetStaticModuleState())

CString csName = strName;
CString csValue = L"";
HRESULT hRet = GetParameterInternal(csName, csValue);
*strValue = csValue.AllocSysString();
CHECK_HRESULT( hRet, E_FAIL )
return S_OK;
}