js浮点数计算精度解决方案

计算加法与减法

/**
 * @params arg1   参与计算的参数1
 * @params arg2   参与计算的参数2
 * @params type   控制加减（true为减法，false为加法）
 * */

function accSub(arg1, arg2, type) {
        let r1, r2, m, n;
        try {
          r1 = arg1.toString().split(".")[1].length;
        } catch (e) {
          r1 = 0;
        }
        try {
          r2 = arg2.toString().split(".")[1].length;
        } catch (e) {
          r2 = 0;
        }
        // console.log(r1,r2);
        m = Math.pow(10, Math.max(r1, r2)); //last modify by deeka //动态控制精度长度
        n = (r1 >= r2) ? r1 : r2;
        console.log(m);
        console.log(n);
        return !type ? ((arg1 * m + arg2 * m) / m).toFixed(n) : ((arg1 * m - arg2 * m) / m).toFixed(n)
      }

计算乘法

function accMul(curr,next){
    let m=0,s1=curr.toString(),s2=next.toString();
    try{m+=s1.split(".")[1].length}catch(e){}
    try{m+=s2.split(".")[1].length}catch(e){}
    return Number(s1.replace(".",""))*Number(s2.replace(".",""))/Math.pow(10,m)
  }

计算除法

function accDiv(curr, next) { //去小数点，扩大倍数，再乘以相应倍数
    let t1 = 0, t2 = 0, curr_l, next_l;
    try {
      t1 = curr.toString().split(".")[1].length;
    }
    catch (e) {
    }
    try {
      t2 = next.toString().split(".")[1].length;
    }
    catch (e) {
    }
    curr_l = Number(curr.toString().replace(".", ""));
    next_l = Number(next.toString().replace(".", ""));
    return (curr_l / next_l) * Math.pow(10, t2 - t1);
  }