演示 TS

class SingleTon {
  name: string
  private constructor(name: string) {
    this.name = name;
  }
  private static instance: SingleTon | null = null
  static getInstance(name: string): SingleTon {
    if (this.instance === null) {
      this.instance = new SingleTon(name);
    }
    return this.instance;
  }
}
const s1 = SingleTon.getInstance('zwx'); // 正确获取单例对象的方式
// new SingleTon(); // 无法在外部实例化 会报错
const s2 = SingleTon.getInstance('zwx2');
console.log(s1 === s2, s1.name, s2.name) // true zwx zwx