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The Code Is Always Associated With a Component

A Visual LANSA application consists of several individual event-routines which are associated with specific components.
This is quite different from a LANSA function which is a single program in which DISPLAY, REQUEST and POP_UP commands create entire screens. These screens are always processed as a whole.
In contrast, in Visual LANSA every component on a form can have its own event routine which gets executed independently when the user performs a certain action. Because of this, you can create dynamic interfaces which instantly respond to user actions. For example you can disable and enable controls depending on the user's choices:

In a LANSA function you cannot change the screen dynamically because it is processed as a whole. The information entered on a screen is processed and validated only when the user clicks on the OK button:

 
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