Iuknown interface, DOT NET Programming

Describe IUKNOWN interface

All COM object supports atleast one interface, that is  IUnknown interface. All interfaces are the classes, derived from the base class IUnknown. Every interface supports methods access data and perform operations transparently to the programmer. taking example, IUnknown supports 3 methods, AddRef, Release(), & QueryInterface(). Assuming that pinterf is a pointer to an IUnknown. pinterf->AddRef() increments the reference count. pinterf->Release() decrements the reference count, deleting the object when the reference count reaches 0(zero). pinterf->QueryInterface( IDesired,pDesired) checks to watch  if the current interface (IUnknown) supports another interface, IDesired, creates an instance (via a call to CoCreateInstance()) of the object if the reference count is 0 (the object does not yet exist), and then calls pDesired->AddRef() to increment the reference count (where pDesired is a pointer to IDesired) and returns the pointer to the caller.

Posted Date: 9/21/2012 7:26:27 AM | Location : United States







Related Discussions:- Iuknown interface, Assignment Help, Ask Question on Iuknown interface, Get Answer, Expert's Help, Iuknown interface Discussions

Write discussion on Iuknown interface
Your posts are moderated
Related Questions
What is the difference between int and int32. There is no difference among int and int32. System.Int32 is a .NET Class and int is an alias name for System.Int32.

What is a gateway or Router? A node that is linked to two or more networks is commonly called as router or Gateway. It generally forwards message from single network to another

I have the working code I''m using to print the SQL table right now. I just need code to print in reverse order.

I need mt4 programmer Project Description: I'm seeking a professional programmer to teach me MQL I have few years experience in manual trading but totally NONE in MT4 / EA

In this assignment you will create a Windows application that mimic the ILDASM application. Your application should have at least the following features: 1. A multi-form applica

Mention the execution process for managed code. A piece of managed code is executed as follows:     Choosing a language compiler     Compiling the code to MSIL     Com

Ask question #Minimum 100 words accepWrite an ASP.NET program that allows you to create and populate a CheckBoxList control by accessing the Title field from the Movies database ta

Problem: (a) Define the term ViewState as used in the ASP.NET framework. (b) What is a StateBag class? Give a simple example to support your answer. (c) (i) Distingui

How is a property designated as read-only?  In VB.NET: Public Read-Only Property Property Name  As Return Type Get ?Your Property execution goes in here End Get End Property.

Import Columns of Data into Data Table for Data Grid View in C# and WPF Need help with a project in C# / WPF. Trying to read a csv file or text file with columns of data that wi