First, place a canvas element in the html page, where the canvas element should have three attributes: ID, width, and height.
Get the canvas object and get the context var cxt=document.getElementById('demo').getContext("2d"); The parameter 2d is determined.
Start drawing. There are two forms, one is fill and the other is stroke.
javascript code:
Rendering:
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
