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<!DOCTYPE html> <html> <body> <h1>JavaScript 类没有被提升</h1> <p>如果在声明类之前尝试使用类，则会出现错误。</p> <p id="demo"></p> <script> //You cannot use the class yet. //myCar = new Car("Ford") //This would raise an error. class Car { constructor(brand) { this.carname = brand; } } //Now you can use the class: let myCar = new Car("Ford") </script> </body> </html>