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Miraplacid Forum >> Software Development >> _bstr_t vs CComBSTR, _variant_t vs CComVariantModerator:XMan

Author Topic:  _bstr_t vs CComBSTR, _variant_t vs CComVariant

From: Canada
posted 2004-05-14 12:10:25 Reply -Delete

Do you use _bstr_t and _variant_t or CComBSTR and CComVariant? Fucntionality looks pretty the similar, but _xxx_t has some extras. I use CComXXX cause ATL does ...
Does it make sense to switch? What you think?


From: US
posted 2004-05-15 04:25:30 Reply -Delete

Do you use Visual Studio 6 or 7? In VS 6 _bstr_t is useless for programms other than Hello World. There is no Detach. In VS 7 - of course _bstr_t.


From: Suomi
posted 2004-06-04 09:29:29 Reply -Delete

It seems, Variant and BSTR wrappers have been written by different guys.
In _bstr_t Attach really attaches to the BSTR. In _variant_t it just make a copy and releases the original one which is disaster when you write put_something code.
CComVariant does not have such kind of problems, but ATL wrappers have another disease. CComBSTR::Copy makes a copy of the object while CComVariant::Copy does the opposit thing - it works like assignment operator.

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