com中的字符串

com中的字符串

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BSTR
:Its header 4 bytes contain length of string (number of bytes, excluding the terminating null bytes ), and are followed by unicode string data.

API
SysAllocString
SysFreeString
SysStringLen
SysStringByteLen

MFC and ATL provide some smart classes:

 CComBSTR, _bstr_t,

which will help you release memory.
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Variant

API
VariantInit
VariantClear
VariantChangeType
VariantCopy

MFC and ATL provide some smart classes to govern VARIANT data type. They are:

CComVariant
_variant_t
COleVariant

<VARIANTARGs >
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