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CComBSTR::CComBSTR

The constructor. The default constructor sets the m_str member to NULL.

CComBSTR( ) throw( ); 
CComBSTR( 
   const CComBSTR& src  
); 
CComBSTR( 
   REFGUID guid  
); 
CComBSTR( 
   int nSize  
); 
CComBSTR( 
   int nSize, 
   LPCOLESTR sz  
); 
CComBSTR( 
   int nSize, 
   LPCSTR sz  
); 
CComBSTR( 
   LPCOLESTR pSrc  
); 
CComBSTR( 
   LPCSTR pSrc  
);

Parameters

  • nSize
    [in] The number of characters to copy from sz or the initial size in characters for the CComBSTR.

  • sz
    [in] A string to copy. The Unicode version specifies an LPCOLESTR; the ANSI version specifies an LPCSTR.

  • pSrc
    [in] A string to copy. The Unicode version specifies an LPCOLESTR; the ANSI version specifies an LPCSTR.

  • src
    [in] A CComBSTR object.

  • guid
    [in] A reference to a GUID structure.

Remarks

The copy constructor sets m_str to a copy of the BSTR member of src. The REFGUID constructor converts the GUID to a string using StringFromGUID2 and stores the result.

The other constructors set m_str to a copy of the specified string. If you pass a value for nSize, then only nSize characters will be copied, followed by a terminating null character.

The destructor frees the string pointed to by m_str.

Example

CComBSTR bstr1;   // BSTR points to NULL
bstr1 = "Bye";    // initialize with assignment operator 
                  // ANSI string is converted to wide char

OLECHAR* str = OLESTR("Bye bye!");  // wide char string of length 5 
int len = (int)wcslen(str);
CComBSTR bstr2(len + 1);// unintialized BSTR of length 6
wcsncpy_s(bstr2.m_str, bstr2.Length(), str, len); // copy wide char string to BSTR

CComBSTR bstr3(5, OLESTR("Hello World")); // BSTR containing 'Hello',  
                                          // input string is wide char
CComBSTR bstr4(5, "Hello World");         // same as above, input string  
                                          // is ANSI

CComBSTR bstr5(OLESTR("Hey there")); // BSTR containing 'Hey there',  
                                     // input string is wide char
CComBSTR bstr6("Hey there");         // same as above, input string  
                                     // is ANSI

CComBSTR bstr7(bstr6);     // copy constructor, bstr7 contains 'Hey there'   

Requirements

Header: atlbase.h

See Also

Reference

CComBSTR Class

Other Resources

ATL and MFC String Conversion Macros