在 TypeScript 中,修饰符(Modifier)是用于控制类、属性、方法等成员访问权限的关键字。TypeScript 提供了以下几种修饰符:
下面是一个使用这些修饰符的例子:
class Person {
public name: string;
private _age: number;
protected department: string;
readonly birthYear: number;
static companyName: string = 'Acme Inc.';
constructor(name: string, age: number, department: string, birthYear: number) {
this.name = name;
this._age = age;
this.department = department;
this.birthYear = birthYear;
}
private getAge(): number {
return this._age;
}
public introduce(): void {
console.log(`Hi, my name is ${this.name} and I'm ${this.getAge()} years old. I work in the ${this.department} department at ${Person.companyName}.`);
}
static getCompanyName(): string {
return Person.companyName;
}
}
let john = new Person('John Doe', 30, 'Engineering', 1990);
john.name; // 'John Doe' (public)
john._age; // Error: '_age' is private
john.department; // 'Engineering' (protected)
john.birthYear; // 1990 (readonly)
Person.companyName; // 'Acme Inc.' (static)
john.getAge(); // Error: 'getAge' is private
Person.getCompanyName(); // 'Acme Inc.' (static method)
在这个例子中:
修饰符在 TypeScript 中非常重要,它们可以帮助开发者控制类、属性和方法的访问权限,从而提高代码的可维护性和安全性。合理使用修饰符可以确保代码遵循面向对象编程的封装原则,防止意外的访问和修改。