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CS-1201 Object Oriented Programming Classes, Objects and Constructors Arbish Akram Department of Computer Science Government College University Arbish Akram 1 / 17 Classes...

CS-1201 Object Oriented Programming Classes, Objects and Constructors Arbish Akram Department of Computer Science Government College University Arbish Akram 1 / 17 Classes A class is a user-defined data type that acts as a blueprint for creating objects. It encapsulates data for the object (attributes) and methods to manipulate that data (functions). A class typically defines: Attributes: Variables that hold the state of an object. Methods: Functions that define the behavior of the object. Classes do not occupy memory until an object is created (instantiated). Think of a class as a plan, template, or blueprint. Arbish Akram 2 / 17 Objects An object is an instance of a class, meaning it is created based on the class definition. Objects hold specific data that conforms to the structure defined by their class. Each object can have unique values for its attributes. Key characteristics: State: Defined by the values of the object’s attributes. Behavior: The actions (methods) the object can perform. Identity: Each object is distinct, even if its state and behavior are identical to another object. Think of an object as a real-world entity created from a blueprint (class). Arbish Akram 3 / 17 Class A class can be visualized as a three-compartment box. 1 Class name (or identifier): identifies the class. 2 Data Members or Variables (or attributes, states, fields): contains the static attributes of the class. 3 Member Functions (or methods, behaviors, operations): contains the dynamic operations of the class. Arbish Akram 4 / 17 Class Arbish Akram 5 / 17 Class Arbish Akram 6 / 17 Class Arbish Akram 7 / 17  Class A class is a user-defined data type in C++ that serves as a blueprint for creating objects. It encapsulates data members (attributes) and member functions (methods) into a single unit. Help in organizing code and promoting reusability. 1 class Car { 2 3 public: 4 string brand; 5 string model; 6 int year; 7 8 void start() { 9 cout