What do you mean by object?
An object is a fundamental concept in programming that represents a specific instance of a class. It combines data (attributes) and behaviors (methods) into a single unit.
Think of a class as a blueprint or template for creating objects. Just like how a blueprint for a house defines its structure and layout, a class defines the structure and behavior of objects. An object is like an actual house built based on that blueprint.
For example, consider a class "Car" that has attributes like "color" and "model," and methods like "startEngine" and "drive." When you create an object from this class, you're creating a real instance of a car with a specific color and model, and you can make it do things like starting the engine and driving.
Here's a breakdown of what an object is:
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Data (Attributes): An object has data associated with it. These data items are known as attributes or properties. Attributes represent the characteristics or state of the object. For example, if you have a Person class, the attributes could include the person's name, age, and address.
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Behavior (Methods): Objects can perform actions or operations. These actions are defined as methods in the class. Methods define the behavior of the object. For instance, a Person object might have methods like Introduce() and GetBirthYear().
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Encapsulation: Objects encapsulate data and behavior together, ensuring that the data is accessed and modified through defined methods. This concept helps in maintaining data integrity and control over how data is used.
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Instance of a Class: An object is created based on a class blueprint. The class defines the structure of the object, including its attributes and methods. When you create an object from a class, you're instantiating that class, and the object becomes an instance of that class.
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Identity: Each object has a unique identity. Even if two objects have the same data, they are considered distinct because they represent separate instances.
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Interactions: Objects can interact with each other by invoking each other's methods, exchanging data, and collaborating to achieve desired functionalities.
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Abstraction: Objects abstract the complexities of real-world entities into manageable components in software. They allow you to focus on specific aspects of an entity without needing to understand all the details.
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Reuse and Modularity: Objects promote code reusability and modular design. You can create a class once and then create multiple instances of that class, each representing a unique object.
In summary, an object is a fundamental building block in object-oriented programming, representing a combination of data and behavior that can be instantiated from a class. Objects allow you to model real-world entities and solve complex problems in a structured and organized manner.
Let's consider a "Student" class as an illustration. The attributes such as "Id," "FirstName," and "LastName" define the characteristics of the object. However, the true essence of being a student involves the action of taking exams. Therefore, "TakeTheExam" represents the function or behavior associated with the student object.
Now we create an object of the class by using 'new' keyword and then we can access all the members of class as mentioned below: