>hi all,
>
>i need to learn via step by step ,how i can use baseform(class already exist) at the main form, or it must be for evry form.

First you should have a clear idea of a class hierarchy. It is best if you have a base form, from which every other form is derived. I'll call this base form class cForm.

However, the inheritance can be indirect - another class derives from class cForm, and your end forms derive from that other class. For example, you can have a class called cModal for modal forms, or a class cDataForm for forms that manage data.

To create another class based on the original class:

Open the project manager

Select "Classes"

Select a class library where you want to save your new class. This is not necessary if you want to create a new class library.

Click on "New". Under "Class name", indicate a name for the new class (for example, "cModal"), under "Based on" click on the "..." button to the right and select the class library. If it is a new class library, give it a name under "Store in".

Start to modify your new class.

To create a form based on a form class, look at the help under "create form". For example:

create form MyNewForm as cModal from MyFormClasses

After creating the first form, I often found it convenient to just make a copy of the form for new forms, and modify the copy.

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