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("ta ta"); // 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