javascript - 在 typescript 中删除键值对的正确方法是什么

Question

我进行了以下实验，发现 'delete' 可用于删除键值对。我的问题是:这是“正确”的做法吗？

let myMap:{[key:string]:string} = {};

myMap["hello"] = "world";
console.log("hello="+myMap["hello"]); // it prints 'hello=world'

delete myMap["hello"];
console.log("hello="+myMap["hello"]); // it prints 'hello=undefined'

Answer 1

My question is: is this the 'proper' way to do it?

这是正确的做法，但是有 two caveats

• 除非该属性不可配置
• 属性(property)继承

例如您不能删除location的href属性

delete location.href //returns false since this property cannot be deleted

演示

var b = {
  a: 1,
  b: 2
};
Object.defineProperty(b, "c", {
  enumerable: true,
  configurable: false,
  writable: true,
  value: 3
});
delete b.c;
console.log(b); //all properties intact