Expalin class in javascript with example and outputs
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Welcome to JavaScript classes! A class is like a blueprint or template for creating objects. Think of it as a cookie cutter that helps you make multiple cookies with the same shape. Classes contain a constructor to initialize new objects, methods to define behavior, and properties to store data. Let's explore how classes work in JavaScript.
Let's look at the basic syntax of a JavaScript class. We start with the class keyword followed by the class name. The constructor method is special - it runs when we create new objects. Inside the constructor, we use 'this' to set properties. Methods like greet and celebrate define what objects can do. To create objects, we use the 'new' keyword followed by the class name and any parameters.
Here's a practical example with a Car class. The constructor takes brand, model, and year parameters and sets up initial properties including a boolean for tracking if the car is running. We define methods for starting and stopping the car, plus getting car information. When we create two car objects and call their methods, we see how each object maintains its own data while sharing the same behavior defined in the class.
To summarize what we've learned about JavaScript classes: Classes serve as templates that define the structure and behavior for objects. The constructor method sets up initial properties when new objects are created. Methods provide shared functionality that all instances can use. By using the new keyword, we create individual objects that maintain their own data while inheriting the class behaviors. This makes classes a powerful tool for organizing and reusing code in JavaScript applications.
Let's look at the basic syntax of a JavaScript class. We start with the class keyword followed by the class name. The constructor method is special - it runs when we create new objects. Inside the constructor, we use 'this' to set properties. Methods like greet and celebrate define what objects can do. To create objects, we use the 'new' keyword followed by the class name and any parameters.
Here's a practical example with a Car class. The constructor takes brand, model, and year parameters and sets up initial properties including a boolean for tracking if the car is running. We define methods for starting and stopping the car, plus getting car information. When we create two car objects and call their methods, we see how each object maintains its own data while sharing the same behavior defined in the class.
To summarize what we've learned about JavaScript classes: Classes serve as templates that define the structure and behavior for objects. The constructor method sets up initial properties when new objects are created. Methods provide shared functionality that all instances can use. By using the new keyword, we create individual objects that maintain their own data while inheriting the class behaviors. This makes classes a powerful tool for organizing and reusing code in JavaScript applications.
JavaScript classes support advanced features like inheritance using the extends keyword. Child classes can call parent methods with super and override them as needed. Static methods belong to the class itself, not instances. Private fields use the hash symbol for encapsulation. These features make JavaScript classes powerful tools for building complex, maintainable applications with proper object-oriented design patterns.