用这个方法会提示 ‘month’ is constant. 正确用法：用let定义一个变量
// const date = new Date(); // const d = date.toLocaleDateString() // console.log(d) // 2020-9-3
const data = new Date(); const year = data.getFullYear(); const month = data.getMonth() + 1; // 记得当前月是要+1的 const dt = data.getDate(); let m = ''; let d = ''; if (month <= 9) { console.log(`0${month}`) m = `0${month}` } if (dt <= 9) { console.log(`0${dt}`) d = `0${dt}` } const today = `${year}-${m}-${d}`; console.log(today); // 2020-09-03