|
VariantClear
pvarg)
VARIANTARG FAR* pvarg
Clears a variant.
Parameter
pvarg
Pointer to the VARIANTARG to clear.
Return Value
The SCODE obtained from the returned HRESULT is one of the following:
SCODE
| Meaning
| S_OK
| Success.
| DISP_E_ARRAYISLOCKED
| The variant contains an array that is locked.
| DISP_E_BADVARTYPE
| The variant type pvarg is not a valid type of variant.
| E_INVALIDARG
| One of the arguments is invalid.
|
Comments
This function should be used to clear variables of type VARIANTARG (or
VARIANT) before the memory containing the VARIANTARG is freed (as when a local
variable goes out of scope).
The function clears a VARIANTARG by setting the vt field to VT_EMPTY and the wReserved field to 0. The current contents of the VARIANTARG are released first. If the vt field is VT_BSTR, the string is freed; if the vt field is VT_DISPATCH, the object is released. If the vt field has the VT_ARRAY bit set, the array is freed.
In certain cases, you may prefer to clear a variant in your own code, without
calling VariantClear. For example, it is permissible to change the type of a VT_I4 variant to some
other type without calling this function. However, you must call VariantClear if you receive a VT_type that you are not prepared to handle. Using VariantClear in these cases ensures that your code will continue to work if OLE Automation
adds new variant types in the future.
Example
for(i = 0; i < celt; ++i)
VariantClear(&rgvar[i]);
Related LinksSoftware for Delphi and C++ Builder developers
Software for Visual Studio .NET developers
Software for Visual Basic 6 developers
Delphi Tips&Tricks
MegaDetailed.NET
TMS Scripter Studio Pro components for Delphi/C++Builder
More Online Helps Win32 Programmer's Reference (win32.hlp)
Win32 Multimedia Programmer's Reference (mmedia.hlp)
Microsoft Windows Pen API Programmer's Reference (penapi.hlp)
Microsoft Windows Sockets 2 Reference (sock2.hlp)
Microsoft Windows Telephony API (TAPI) Programmer's Reference (sock2.hlp)
Unix Manual Pages
|
