JavaScript is a widely used scripting language, often used for dynamic effects and performance in web pages, such as solving rectangles. In this article, we will introduce how to use JavaScript to complete the process of finding a rectangle. Let’s introduce it step by step below!
- How to define a rectangle
First, we need to define the dimensions of the rectangle. We can use variables in JavaScript to represent the length and width of a rectangle. Here, we define a rectangle class and implement methods to get the length and width.
class Rectangle { constructor(length,width){ this.length = length; this.width = width; } getLength(){ return this.length; } getWidth(){ return this.width; } }
In this class, we set two attributes, length and width. These two properties determine the size of the rectangle. In the constructor of the class, we pass in these two parameters and assign them to the properties in the class. Next, we defined two methods, getLength() and getWidth(), to obtain the length and width values.
- How to find the perimeter of a rectangle
Next, we need to calculate the perimeter of the rectangle. According to the formula, the perimeter of a rectangle can be calculated by adding the length and width respectively and multiplying by 2. We can add a method to the Rectangle class to implement this process.
class Rectangle { constructor(length,width){ this.length = length; this.width = width; } getLength(){ return this.length; } getWidth(){ return this.width; } perimeter(){ return 2*(this.length + this.width); } }
In the perimeter() method, we calculate the sum of the length and width and multiply it by 2 to get the perimeter of the rectangle. Using this method, we can easily get the perimeter of a rectangle.
let rectangle = new Rectangle(10,15); console.log(rectangle.perimeter()); // 输出40
Here, we create a rectangle with a length of 10 and a width of 15, and then use the perimeter() method to calculate the perimeter of the rectangle. The result is 40.
- How to find the area of a rectangle
Finally, we need to find the area of the rectangle. According to the formula, the area of a rectangle can be calculated by multiplying the length and width. We can add a method to the Rectangle class to implement this process.
class Rectangle { constructor(length,width){ this.length = length; this.width = width; } getLength(){ return this.length; } getWidth(){ return this.width; } perimeter(){ return 2*(this.length + this.width); } area(){ return this.length * this.width; } }
In the area() method, we multiply the length and width to get the area of the rectangle. Using this method, we can easily get the area of a rectangle.
let rectangle = new Rectangle(10,15); console.log(rectangle.area()); // 输出150
Here, we created a rectangle with a length of 10 and a width of 15, and then used the area() method to calculate the area of the rectangle. The result is 150.
Summary
In this article, we use JavaScript to implement the process of finding a rectangle. First, we define the rectangle class and implement methods to get the length and width. Next, we calculated the perimeter and area of the rectangle, using the perimeter() and area() methods respectively. Using these methods, we can easily solve the rectangle. Hope this article helps you!
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