js 数字类型取整方法

let num = 1.75

1.向上取整

let result = Math.round(num)

console.log(result) // 结果为 2

2.四舍五入

let result = Math.ceil(num)

console.log(result) // 结果为 2

3.向下取整

let result = Math.floor(num)

console.log(result) // 结果为 1