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Why not use class fields directly?

So, I know that classes and structures are data structures. Class fields are private by default and structural are public. Both public: / int a;for C ++ and public int a;C #

But other ways to access these fields are that they are private and use functions / methods. How SetValue(int value){a = value;}and GetValue() { return a; }or I even heard about a cool new {set; get;}in C #.

But why? Many people have told me that "other people can access your variables this way, so make them private." I don’t understand what difference makes them public and just uses them obj.a = 3;or makes them private and makes obj.SetValue(3);? Can someone (at least briefly) explain what the differences are and how so can get into these fields when they are open?

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8 answers

There are many reasons why you would like to use properties (getters and setters) instead of public fields (instance variables have been published). Some of them:

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   }
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}

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