When writing an event-handling method in a GUI application, what should you consider about a variable's scope?
What will be an ideal response?
When you create event-handling methods in a GUI application, you must constantly be aware of which variables and constants are needed by multiple methods. When you declare a variable or constant within a method, it is local to that method. If a variable or constant is needed by multiple event-handling methods-for example, by two different Click() methods-then the variables or constants in question must be defined outside the methods (but within the Form class) so that both Click() methods have access to them. When you write other methods, you can decide what arguments to pass in. But automatically generated event-handling methods have predefined sets of parameters, so you cannot be as flexible in using them as you can with other methods you write.
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