JS 如何实现类似java的movePointLeft方法移动小数点位置

Question

给定一个数字，在给定一个指定移动位数

let movePointLeft = (n, m) => {
    //???
}
let num = 50;

movePointLeft(num,3) //==> 0.05
movePointLeft(num,2) //==> 0.5
movePointLeft(num,1) //==> 5
movePointLeft(num,0) //==> 50
movePointLeft(num,-1) //==> 500
movePointLeft(num,-2) //==> 5000

Answer 1

• Math.pow(10, n) 可以计算 10 的 n 次方
• 再用一个除法

Answer 2

function movePointLeft(n, m) {
    return +n * Math.pow(10, -m);
}
console.dir(movePointLeft(50, 3));