JS Singleton

Singleton

只能创建一个实例对象

const Singleton = (function(){
  let instance;

  function createInstance(){
    const object = new Object({name:'brad'});
    return object;
  }

  return {
    getInstance:function(){
      if(!instance){
        instance = createInstance();
      }
      return instance;
    }
  }
})();

const instanceA = Singleton.getInstance();
const instanceB = Singleton.getInstance();


console.log(instanceA ===instanceB);  //True
//只能创建一个instance