Hello there! Today, we're delving into TypeScript classes, focusing on attributes and methods. Attributes define properties, whereas methods define actions. Through the Dog class, you'll learn these concepts. By the end of the lesson, you should be capable of effectively using attributes and methods in TypeScript classes.

Attributes can be regarded as properties. For a Dog class, the attributes can include name: "Fido", breed: "Poodle", color: "White". These attributes depict a dog's characteristics, such as those of Fido.

In the Dog class, we define attributes like name, breed, and color directly. These attributes represent a dog's characteristics and are set with default values:

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1class Dog {
2    name: string = 'Fido';
3    breed: string = 'Poodle';
4    color: string = 'White';
5}

To instantiate the class and access these attributes, you would do the following:

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1let fido = new Dog();
2
3console.log(fido.name);  // Prints: Fido
4console.log(fido.breed); // Prints: Poodle
5console.log(fido.color); // Prints: White

Here, Fido is an object of the Dog class.

Methods are actions that instances of a class can execute. For the Dog class, behaviors might include bark(), eat(), and sleep(). These methods are functions defined in the class.

Let's enrich Fido's life with some actions. By introducing methods to the Dog class, we can enable him to bark, eat, and sleep:

TypeScript
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1class Dog {
2    name: string = 'Fido';
3    breed: string = 'Poodle';
4    color: string = 'White';
5
6    bark() {
7        console.log('Woof Woof!');
8    }
9
10    eat(food: string) {
11        console.log(`${this.name} is eating ${food}.`); // "this" refers to the current instance of the Dog class, referencing the class attribute.
12    }
13
14    sleep() {
15        console.log('Zzz...');
16    }
17}

Here, the bark, eat, and sleep methods determine a Dog object's behavior. Now, an instance of Dog can bark, eat, and sleep. Note the usage of this in the eat(food: string) method - here this refers to the current instance of the Dog class, referencing the class attribute.

Let's create an object from the Dog class and call its methods:

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1let fido = new Dog();
2
3console.log(fido.name); // Prints: Fido
4console.log(fido.breed); // Prints: Poodle
5console.log(fido.color); // Prints: White
6
7fido.bark(); // Prints: Woof Woof!
8fido.eat("bone"); // Prints: Fido is eating bone.
9fido.sleep(); // Prints: Zzz...

Equipped with attributes and methods, our Dog class truly comes alive!

That's about it! With attributes and methods, you can render TypeScript classes more interactive. In this lesson, the Dog class served to demonstrate the application of attributes and methods. Up next are exercises tailored for you to practice and hone these learned concepts. Happy coding!