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In this video, we'll discuss another way to create objects in c++

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using a struct or structure.

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The struct comes from the c programming language.

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In c, we create structs as a container for data,

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much like a record in many other programming languages.

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C++ also supports struct since it has to be compatible with c.

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However, it adds the ability to treat structs very much like classes.

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Everything you can do with classes, you can do with structs.

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The only difference is that the members of the structs are public by default.

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Whereas, the members of a class are private by default.

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Here's a simple class declaration for a person class.

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It has a string attribute called name and a method called getname that returns that name.

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By default, class members are private.

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So if we create a p object that's a person

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and try to access name or call getname,

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the compiler will give us a compiler error saying that we don't have access to those private elements.

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Now let's see the same as a struct.

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Here we have person declared as a struct.

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We have the same attribute and the same member method.

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But now when we create the person object p

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and try to access its attribute or member function, the compiler is okay with it.

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That's because the default access for a struct is public.

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That's it.

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That's the only difference between structs and classes in c++.

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But there's a few general guidelines that you can use to determine if you need a structural class.

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It would be appropriate to use a struct when you have passive data.

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So the struct would act very much like a struct in c.

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It simply holds data and that data is public.

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And since the data's passive, you really don't need to create any methods in the struct.

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As for a class we've already seen many examples.

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If your objects are active or they have complex behavior,

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then you should use a class and implement getters and setters and member methods as needed.

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These guidelines are very general. But remember,

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other c++ programmers will likely be modifying and extending your code.

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So don't use c++ in a way that's very different

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from what c++ programmers expect.

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For example, don't use a struct and then make everything

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private in the struct so it behaves like a class, just use a class instead.