Microsoft Component Object Model Flaw Gives Hackers Easy Access to Windows Microsoft often talks up the security of Windows 10, but like any platform these days it has its fair share of problems. An EXCELLENT treatment of the subject of programming Microsoft's Component Object Model. This is a book for COM programmers who want to get to know the subject of COM from the bottom up. Microsoft Excel supports a Programming Object Model (OM) for developers to use to automate and control Excel behavior. The OM was originally designed for Visual Basic for Applications (VBA) macros, but is also used by most add-in types, such as Component Object Model (COM) Add-Ins, managed (.NET) Add-Ins, Visual Studio Tools for Office (VSTO) document and application level customizations,. If you are a developer, at some point you may need to load or unload a Component Object Model (COM) add-in. Important: If you are not a developer, you should not have any occasion to use this procedure. If you need installation and removal instructions for a COM add-in, contact the person who. 'Don Box makes it possible for mere mortals to join the COM cognoscenti. If youire a C++ COM programmer, buy this book.' -David Chappell, Principal, Chappell & Associates and author of Understanding ActiveX and OLE Written by a leading COM authority, this unique book reveals the essence of COM, helping developers to truly understand the why, not just the how, of COM. Understanding the motivation for the design of COM and its distributed aspects is critical for developers who wish to go beyond simplistic applications of COM and become truly effective COM programmers. As the COM programming model continues to evolve, such insight also becomes essential to remaining current with extensions, such as Microsoft Transaction Server and COM+. By showing you why Distributed COM works as it does, Don Box enables you to apply the model creatively and effectively to everyday programming problems. This book examines COM from the perspective of a C++ developer, offering a familiar frame of reference to ease you into the topic. You will also find comprehensive coverage of the core concepts of Distributed COM (interfaces, classes, apartments, and applications), including detailed descriptions of COM theory, the C++ language mapping, COM IDL (Interface Definition Language), the remoting architecture, IUnknown, monikers, threads, marshalers, security, and more. In addition, the book offers a thorough explanation of COMis basic vocabulary, provides a complete Distributed COM application to illustrate programming techniques, and includes the authoris tested library of COM utility code. Don Box is a leading educator, recognized authority on the Component Object Model (COM), coauthor of the Simple Object Access Protocol (SOAP) specification, and coiner of the term 'COM is Love.' Colors serial mohe rang de lal. He recently joined Microsoft as an architect in the Microsoft®.NET Developer and Platform Evangelism Group. Earlier in his career, Box cofounded DevelopMentor Inc., a component software think tank aimed at educating developers on the use of the COM, Java, and XML. A popular public speaker, Box is known for engaging audiences around the world, combining deep technical insight with often outrageous stunts. Com Component Object ModelSandra echeverria y marc anthony la fuerza del destino download free. • Firstly, COM is just like object-oriented programming. COM interface is an abstract interface. • COM has an advantage over each language's own built-in OOP in that you can have COM classes implemented in different languages and/or compiled by different versions of compilers, and they will still be able to inter-operate. This is called 'application binary interface' (ABI) • COM uses reference counting. It might be annoying at first, but as soon as you learn about smart pointers, your life will be much easier and you will find that the concept of reference counting is very easy to understand. • COM uses a weird way of class casting, namely 'Query Interface'. Learning the is the first step. A good COM interface that is suitable for beginner's study is the IStream interface. You may practice COM by implementing the IStream interface using many kinds of ways of storing data. Added 2012/09/28: After the COM mechanism was invented, people at Microsoft discovered that these mechanisms open the door to unusual programming tricks which are not orthodox OOP. Wiki Component Object ModelAt the lowest level, IUnknown.QueryInterface is just a method; it can do anything. These tricks make COM intimidating to learners, because they can invalidate the basic reasoning that can be borrowed from OOP. The Microsoft documentation at MSDN spends a lot of time saying 'COM is not.' Or 'Make no assumption' explaining how these unusual tricks can break your code. COM designers use Liskov Substitution Principle (the 'L' in ) to make sure their multiple interfaces and use of tricks do not invalidate basic OOP reasoning or program operation. If your project does not use these tricks, it is okay to see COM just from the OOP point of view. If your project uses these tricks, you will need to see COM as self-modifying code. (Joke: We had to spend so much time with L that we typically ignore the four other principles.). The main reason for COM is to provide an object oriented communications interface between an application and other applications and dll's that may live in different memory spaces, and between objects that may have different internal object representations. Something to remember when learning COM is that at the time C++ was king and applications called dll's using C. There was no common ABI (as @rwong says) and COM was the microsoft solution. It's probably worth having a look at Active Template Library (ATL) for visual studio which makes it a bit easier to use COM as well. A couple of books I found useful back in the day hth. I originally learned about COM from the book (DCOM is just an extension of COM, the book is mostly about COM). It's over ten years old and should be cheap if you get it used (since COM isn't exactly hot anymore, not even in the Microsoft world, even though it's still used for interop). The main reason for COM to exist is to facilitate component-based development, which basically means that instead of linking libraries when you compile your code, you reference an interface (the description of how to communicate with an external component) and use some implementation of that when you deploy. It underlies most of Microsoft's own technology. Component Object Model DownloadThe system has support for some features that were cool before everything went managed (such as reference counting and self-description (through IDispatch)). COM is a standard created in the 90's to allow different pieces of software to talk to each other. Most important is the binary standard that allows one piece of software create or bind to an object and then call into that interface. Component Object Model ExamplesThis allows you to do things like create a DLL in C++ which can be called by an ASP page (COM Objects), or create a control in Delphi which you can put onto a VB dialog box (ActiveX controls), or Excel worksheet. When you paste a picture into Word it uses COM too, embedding a separate application into word. Less popular is DCOM which is to call remote objects, there are usually simpler ways to do this. So Com/ActiveX/DCOM was very popular 10 years ago with VB, VBA, C++/ATL, Delphi. Dotnet is much simpler though and C# has replaced most use of COM and VB etc Still there are many COM interfaces in there which exist which you might want to call from a dotnet application or Java or C++. (You dont say) If you need to call COM interfaces VB is the simplest way to do this. In Dotnet 4.0 C# has the dynamic keyword which makes it much easier to call IDispatch interfaces, which is probably a great solution you should look at. If you need to know a lot of detail, you really need to use C++ and ATL, call the C APIs like CoCreateInstance. Avoid this if you can though as its old tech and isn't much use, stick with recommendations above.
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