js 乘除法小数问题

因为经常需要js来处理显示，就做下笔记

除法：

function accDiv(arg1, arg2) {
            var t1 = 0,
                t2 = 0,
                r1, r2;
            try {
                t1 = arg1.toString().split(".")[1].length
            } catch (e) {}
            try {
                t2 = arg2.toString().split(".")[1].length
            } catch (e) {}
            with(Math) {
                r1 = Number(arg1.toString().replace(".", ""))
                r2 = Number(arg2.toString().replace(".", ""))
                return (r1 / r2) * pow(10, t2 - t1);
            }
        }

乘法：

function accMul(arg1, arg2) {
            var m = 0,
                s1 = arg1.toString(),
                s2 = arg2.toString(),
                number,
                z = '';
            try {
                m += s1.split(".")[1].length
            } catch (e) {
                console.log(e);
            }
            try {
                m += s2.split(".")[1].length
            } catch (e) {
                console.log(e);
            }
            console.log(`m = ${m}`)
            number = Number(s1.replace(".", "")) * Number(s2.replace(".", "")) / Math.pow(10, m);
            if (m) {
                try {
                    var n = m - number.toString().split(".")[1].length;
                    if (n) {
                        for (var i = 0; i < n; i++) {
                            z += '0';
                        }
                    }

                        var r = number.toString() + z;
                        return r

                } catch (e) {
                        for (var i = 0; i < m; i++) {
                            z += '0';
                        }
                    var r = number.toString() + '.' + z;
                    return r
                }
            }
            return Number(s1.replace(".", "")) * Number(s2.replace(".", "")) / Math.pow(10, m)
        }

加法：

function accAdd(arg1, arg2) {
            var r1, r2, m;
            try {
                r1 = arg1.toString().split(".")[1].length
            } catch (e) {
                r1 = 0
            }
            try {
                r2 = arg2.toString().split(".")[1].length
            } catch (e) {
                r2 = 0
            }
            m = Math.pow(10, Math.max(r1, r2))
            return (arg1 * m + arg2 * m) / m
        }