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What else can I help you with?
When class will be used and when structure will be used?
In class default members are private and in structure default members are public ,When ever you want to hide data from outside functions then you can use class.But in ANSI C we can hide data by using private access specifier.
Only public member functions can access public member data TrueFalse?
False. Public member data is accessible to all functions, whether they be public, protected or private members of the same class, or they are outside of the class completely.
Encapsulation data we can inherit out side the class?
Yes. If the variables are public yes they can be inherited. If they are private then they cannot be inherited. But to access these private variables you can have accessor methods that are public and can be accessed everywhere.
In ANSI C you can hide data by using private access specifier Justify?
One can always declare a datatype as static which will limit the scope to the file only. this way data hiding can be achived. For more clearance on the same please refer 'the C programming language'. Data hiding means only relevant data is visible to the user and all the background information is hidden from the user. In c++, the variables are named as data members and these can be hidden with the help of private access specifier. In procedural languages, variables(global variables) are free to flow from functions to functions and hence they were not secured. But in C++, only the class in which the data members are being declared can access them by using private specifier. As, the data members and also member functions of a class cannot be accessed outside the class if they have private access so, they get hidden from the user and hence the data hiding is achieved. Also in inheritance when we derive a class from the base class then the derived class cannot access the private members of the base class. In addition, if a class is derived from another class privately i.e. for example syntax : class B : private A , is used then all the public and protected members (not private) becomes private to class B and cannot be accessed outside the class B, even by using the object of class B. Hence, data hiding is achieved in C++ through private access specifier.
How can you access private functions of a class from the Main function in Cpp?
Any member functions and data members declared as 'private' in a class, can only be accessed directly by functions within the class.They cannot be accessed directly by derived objects, nor from anywhere outside an object of the class, such as from the Main function.To access private class members, you must rely on what are called accessor functions. Accessor functions are functions inside the class, either public or protected, which automatically have access to private members.If a function from Main, or elsewhere outside the class hierarchy, needs access, then you need to use publicaccessor functions. For derived class access, you can use protected accessor functions.
How does a class in c plus plus enforce data encapsulation?
Data encapsulation is enforced by restricting access to the class members. Access can be specified on a per-member basis, defaulting to private access for a class and public access for a struct. Private members are accessible to class members and to friends of the class. Protected members are the same as private members but are also accessible to derived class members. Public members are fully-accessible. Data members are typically declared private while interfaces are typically declared public or protected.
What is classes in programing?
There are no classes in C; it is not an object-oriented programming language. C++ has classes. A class is a data type from which objects can instantiated in much the same way that an integer variable can be instantiated from an int data type in both C and C++. However, an int is a primitive data type; it has no member methods associated with it. The built-in operators are designed to operate upon primitive data types but those operators are not integral to the type. A class is more like a struct in C; an aggregate of data values. A class can contain both static data (data that is common to the class) and non-static data (data that relates to an instance of the class). However, as well as storing data, a class can also define member functions that operate upon that data, but that are scoped to the class (static member functions) or to an instance of the class (instance member functions). Unlike C where a struct's data members are always public, a C++ class can define separate public, protected and private data members (and functions), where private is the default access. A C++ struct is also a class, but one where the members are public by default. As such, a C++ struct can be used to create trivial "plain old data" classes that are compatible with C code as well as to create highly complex data types. Objects are self-contained entities where the member methods (functions and operators) have private access to the class representation. Non-member functions cannot gain access to this representation other than through public member functions or by being declared a friend of the class. The protected representation is the same as the private representation but is also accessible to derivatives of the class. Derivatives automatically inherit the public and protected members of their base classes, but not the private members. This makes it possible to derive more specialised classes from existing classes without have to duplicate the base class code.
Can Static data members be declared either in the private or public section of class declaration?
Yes. Static members can be private or public. (Or protected.)
What is class in C programming?
There are no classes in C; it is not an object-oriented programming language. C++ has classes. A class is a data type from which objects can instantiated in much the same way that an integer variable can be instantiated from an int data type in both C and C++. However, an int is a primitive data type; it has no member methods associated with it. The built-in operators are designed to operate upon primitive data types but those operators are not integral to the type. A class is more like a struct in C; an aggregate of data values. A class can contain both static data (data that is common to the class) and non-static data (data that relates to an instance of the class). However, as well as storing data, a class can also define member functions that operate upon that data, but that are scoped to the class (static member functions) or to an instance of the class (instance member functions). Unlike C where a struct's data members are always public, a C++ class can define separate public, protected and private data members (and functions), where private is the default access. A C++ struct is also a class, but one where the members are public by default. As such, a C++ struct can be used to create trivial "plain old data" classes that are compatible with C code as well as to create highly complex data types. Objects are self-contained entities where the member methods (functions and operators) have private access to the class representation. Non-member functions cannot gain access to this representation other than through public member functions or by being declared a friend of the class. The protected representation is the same as the private representation but is also accessible to derivatives of the class. Derivatives automatically inherit the public and protected members of their base classes, but not the private members. This makes it possible to derive more specialised classes from existing classes without have to duplicate the base class code.
What are the limitations of friend function in c plus plus?
Only that they cannot be inherited by derived classes. This is "a good thing". Other than that, a friend function has full access to a class' private and protected members and you cannot limit its scope. At this data hiding feature of c++ is broken.
Full data structure information Hindi you?
All is very similar to the declaration on data structures, except that we can now include also functions and members, but also this new thing called access specifier. An access specifier is one of the following three keywords: private, public or protected. These specifiers modify the access rights that the members following them acquire
Difference between structure and class?
Structure members are public by default while class members are private by default. Classes encapsulate the data and the methods that operate upon that data into a discrete package (an object), exposing only as much or as little interface as is required by the class itself, to ensure the data remains in a valid state at all times. Structures have no such protection.
