## JSON.Stringfly()问题
const a = { a: undefined, b: null, c: false, d: 3, e: isNaN };
// const b = Object.assign(a);
const b = JSON.stringify(a);
console.log(b);//{"b":null,"c":false,"d":3}
## JSON.Stringfly()问题
const a = { a: undefined, b: null, c: false, d: 3, e: isNaN };
// const b = Object.assign(a);
const b = JSON.stringify(a);
console.log(b);//{"b":null,"c":false,"d":3}