Types of compatibility in vb6, DOT NET Programming

What are types of compatibility in VB6

There are three possible project compatibility settings:

  • No Compatibility
  • Project Compatibility
  • Binary Compatibility

1) No Compatibility: With this Compatibility setting, new interface ID's, new class ID's,  and a new type library ID will be generated by VB every  time the ActiveX component project is compiled. This will cause any of the compiled client components to fail (with error 429!) and report a missing reference to the 'VB ActiveX Test Component whenever a client project is loaded in the VB IDE.

2) Project Compatibility: With this Compatibility setting, VB will generate a new interface ID's for classes whose interfaces have changed, but will not change the class ID's or the type library ID. This will still cause any of the compiled client components to fail (with error 429!) but will not report a missing reference to the 'VB ActiveX Test Component' whenever  a client project is loaded in the VB IDE. Recompilation of the client components will restore them to the working order again.

3) Binary Compatibility: The VB makes it possible to extend an existing class or interface by adding new methods & properties etc. and yet still remain binary compatibility. It can do this, as it silently creates a new interface ID for the extended interface and adds registration code to register the original interface ID but with a new forward key having the value of this new interface ID. COM will then substitute calls having the old ID with the new ID and so applications built against the old interface will continue to work (assuming the inner workings of the component remain backward compatible!). With that setting, VB will not change any of the existing class, interface or type library ID's, however in order that it can do so, VB requires the project to specify an existing compiled version that it can compare against to assure  that the existing interfaces have not been broken.

Posted Date: 9/21/2012 7:33:53 AM | Location : United States







Related Discussions:- Types of compatibility in vb6, Assignment Help, Ask Question on Types of compatibility in vb6, Get Answer, Expert's Help, Types of compatibility in vb6 Discussions

Write discussion on Types of compatibility in vb6
Your posts are moderated
Related Questions
TSQL Function SQL Server 2012 Project Description: I require someone to prepare a TSQL function that returns the name of the ODBC DSN. I will use the queries below, to get

Project Description: This is an online customization printing system they use for multiple organizations to allow customizing  and access of materials they allocate to drive iss

What is XML? Extensible markup language (XML) is all about describing the data. Below is a XML which describes an invoice data. Shoes   12 10

Question : (a) Explain fully how ADO.NET functions. Illustrate your answer using a diagram. (b) List and explain three methods of the SqlCommand class. (c) Give four o

i want decompile ex5 files Project Description: i want decompile some ex5 files like indicators, scripts and eas i need in format mq5 can do this to me? Skills required

how to create log in form using vb 2010

Finding Largest Array Element - C# Program I am unable to make out the Largest Array Element in C# language. Can anyone suggest me any example for this.

Project Description: I have a website that I have prepared, but I would like someone to make it look nicer. Most of the functionality is there, but I need help with design which

help me to prepare the above charts for my online vegetable selling project

What is UDDI? The Full form of the UDDI is Universal Description, Discovery and Integration. The directory that can be used to publish and discover public Web Services. If you