1.浮点数相加

addFloat(arg1, arg2) {
    var 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;
    }
    m = Math.pow(100, Math.max(r1, r2));
    //动态控制精度长度
    n = (r1 == r2) ? r1 : r2;
    return ((arg1 * m + arg2 * m) / m).toFixed(n);
}

2.浮点数相减

subFloat(arg1, arg2) {
    var 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;
    }
    m = Math.pow(100, Math.max(r1, r2));
    //动态控制精度长度
    n = (r1 == r2) ? r1 : r2;
    return ((arg1 * m - arg2 * m) / m).toFixed(n);
}

3.浮点数相乘

mulFloat(arg1, arg2) {
    var m = 0;

    try {
         m += arg1.toString().split(".")[1].length;
    }
    catch (e) {
    }
    try {
        m += arg2.toString().split(".")[1].length;
    }
    catch (e) {
    }
    return Number(arg1.toString().replace(".", "")) * Number(arg2.toString().replace(".", "")) / Math.pow(10, m);
}

4.浮点数相除

divFloat(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);
    }
}