Today, we will check the difference between public, protected and private for Application Packages.
First, let's check this sample Application Package.
class Person method Person(); method SayBarbecue(); property string Property1; protected method SayHello(); property string Property2; private method SayGoodbye(); instance string &Property3; end-class; method Person end-method; method SayBarbecue MessageBox(0, "", 0, 0, "Barbecue!"); end-method; method SayHello MessageBox(0, "", 0, 0, "Hello!"); end-method; method SayGoodbye MessageBox(0, "", 0, 0, "Goodbye!"); end-method;
We have 3 methods.
- public method: SayBarbecue()
- protected method: SayHello()
- private method: SayGoodbye()
What will happen if we use these methods outside the application class?
The following code has been placed on a FieldChange event.
import TEST_APP_PKG:*; Local TEST_APP_PKG:Person &Lon = create TEST_APP_PKG:Person(); &Lon.SayBarbecue(); /* Cannot be called because these methods are protected or private */ rem &Lon.SayHello(); rem &Lon.SayGoodbye();
SayBarbecue() method can be freely used.
But SayHello() and SayGoodbye() methods will error at compile time.
This is because protected and private methods can only be used within the application class.
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