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ITypeInfo::Invoke

lpvInstance, memid, wFlags, pdispparams, pvargResult, pexcepinfo, puArgErr)
VOID FAR* lpvInstance
MEMBERID memid
unsigned short
wFlags
DISPPARAMS FAR*
pdispparams
VARIANT FAR*
pvargResult
EXCEPINFO FAR*
pexcepinfo
unsigned int FAR*
puArgErr

Invokes a method or accesses a property of an object that implements the interface described by the type description.

Parameters

lpvInstance

Pointer to an instance of the interface described by this type description.

memid

Identifies the interface member.

wFlags

Flags describing the context of the invoke call, as follows:

Value
Description
DISPATCH_METHOD
The member was accessed as a method. If there is ambiguity, both this and the DISPATCH_PROPERTYGET flag may be set.
DISPATCH_PROPERTYGET
The member is being retrieved as a property or data member.
DISPATCH_PROPERTYPUT
The member is being changed as a property or data member.
DISPATCH_PROPERTYPUTREF
The member is being changed by using a reference assignment, rather than a value assignment. This value is only valid when the property accepts a reference to an object.

pdispparams

Points to a structure containing an array of arguments, an array of DISPIDs for named arguments, and counts of the number of elements in each array.

pvargResult

Should be NULL if the caller expects no result; otherwise, it should be a pointer to the location at which the result is to be stored. If wFlags specifies DISPATCH_PROPERTYPUT or DISPATCH_PROPERTYPUTREF, pvargResult is ignored.

pexcepinfo

Points to an exception information structure, which is filled in only if DISP_E_EXCEPTION is returned. If pexcepinfo is NULL on input, only an HRESULT error will be returned.

puArgErr

If Invoke returns DISP_E_TYPEMISMATCH, puArgErr indicates the index (within rgvarg) of the argument with incorrect type. If more than one argument has an error, puArgErr indicates only the first argument with an error. Note that arguments in pdispparams->rgvarg appear in reverse order, so the first argument is the one having the highest index in the array. Can't be NULL.

Return Value

The SCODE obtained from the returned HRESULT is one of the following:

SCODE
Meaning
S_OK
Success.
E_INVALIDARG
One or more of the arguments is invalid.
DISP_E_EXCEPTION
The member being invoked has returned an error HRESULT. If the member implements IErrorInfo, details are available in the error object. Otherwise, the pexcepinfo parameter contains details.
TYPE_E_IOERROR
The function could not read from the file.
TYPE_E_INVDATAREAD
The function could not read from the file.
TYPE_E_UNSUPFORMAT
The type library has an old format.
TYPE_E_REGISTRYACCESS
There was an error accessing the system registration database.
TYPE_E_LIBNOTREGISTERED
The type library was not found in the system registration database.
TYPE_E_INVALIDSTATE
The type library could not be opened.
TYPE_E_WRONGTYPEKIND
Type mismatch.
TYPE_E_ELEMENTNOTFOUND
The element was not found.
TYPE_E_BADMODULEKIND
The module does not support Invoke.
Other returns
Any of the IDispatch::Invoke errors may also be returned.

Comments

Use ITypeInfo::Invoke to access a member of an object or invoke a method that implements the interface described by this type description. For objects that support the IDispatch interface, Invoke can be used to implement IDispatch::Invoke.

ITypeInfo::Invoke takes a pointer to an instance of the class. Otherwise, its parameters are the same as IDispatch::Invoke, except that ITypeInfo::Invoke omits the REFIID and LCID parameters. When called, ITypeInfo::Invoke performs the actions described by the IDispatch::Invoke parameters on the specified instance.

For VTBL interface members, ITypeInfo::Invoke passes the LCID of the typeinfo into parameters tagged with the lcid attribute, and the returned value into the retval parameter.

If the type description inherits from another type description, this function recurses on the base type description if necessary, to find the item with the requested member ID.


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