How to Use structs in COM interfaces when Automation
compatibility is not an issue?
Answer / krishna akkulu
Structs, also known as User Defined Types (UDTs), can be
used in Automation- compatible interfaces
An Automation- compatible struct may contain only primitive
Automation types as its members.
Nesting structs is not allowed, but VARIANT is allowed thus
enabling nested structs (you can store a struct in a
VARIANT).
In order for a struct to be usable for Automation-
compatible interfaces, the struct must be described in a
type library and it must be declared with its own GUID:
[uuid(21602F40-CC62-11d4-AA2B-00A0CC39CFE0)]
struct MyStruct
{
[helpstring("A long value")]
long nLongValue;
[helpstring("A string")]
BSTR bstrStringValue;
};
// Later in the IDL file
[uuid(...), version(...), helpstring(...)]
library MyLib
{
...
struct MyStruct;
};
For more info see : http://vcfaq.mvps.org/com/4.htm
| Is This Answer Correct ? | 0 Yes | 3 No |
What kind of components can be used as DCOM servers?
Can I use com components from .net programs?
Define and explain COM?
Let?s assume we have object B and aggregated object C (in- proc server), created by B. Can you access any interface of B from C? What?s the difference between aggregated and contained objects?
C is aggregated by B, which in turn aggregated by A. Our client requested C. What will happen?
what is mean by scintific,commercial and business applications? How they differ? Please answer me. Advance thanks.
hi,I have applied for NIC test plz if any one have test paper pattrn plz send me on "mn_mayank38@yahoo.co.in"
How can would you create an instance of the object in COM
Explain JIT activation?
What happens when client calls CoCreateInstance?
What are queued components?
Write a JCL to copy only selected members from a partitioned data set to another partitioned data set. (Use: IEBCOPY)