The as Operator

The as operator performs checked typecasts. The expression objectasclass returns a reference to the same object as object, but with the type given by class. At runtime, object must be an instance of the class denoted by class or one of its descendants, or be nil; otherwise an exception is raised. If the declared type of object is unrelated to class - that is, if the types are distinct and one is not an ancestor of the other - a compilation error results. For example, with Sender as TButton do begin Caption := '&Ok'; OnClick := OkClick; end;

The rules of operator precedence often require as typecasts to be enclosed in parentheses. For example,

Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

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