JavaScript小數(shù)、整數(shù)四舍五入方法

    JavaScript小數(shù)、整數(shù)四舍五入方法，具體代碼如下：
    //保留兩位小數(shù)同時四入五入
    function changeTwoDecimal(x) {
    var r = "";
    var x1 = parseFloat(x);
    if (isNaN(x1)) {
    r = x.toString();
    }
    else {
    var x2 = Math.round(x1 * 100) / 100;
    x1 = (x1 * 1000) / 1000;
    if (x2 >= x) r = x2.toString();
    else
    r = (x2 + 0.01).toString();
    }
    var p = r.indexOf('.', 0);
    if (p == -1)
    return r;
    else
    return r.substring(0, p) + r.substring(p, p + 3);
    }
    //保留三位小數(shù)同時四入五入
    function changeThreeDecimal(x) {
    var r = "";
    var x1 = parseFloat(x);
    if (isNaN(x1)) {
    r = x.toString();
    }
    else {
    var x2 = Math.round(x1 * 1000) / 1000;
    x1 = Math.round(x1 * 10000) / 10000;
    if (x2 >= x1) r = x2.toString();
    else
    r = (x2 + 0.001).toString();
    }
    var p = r.indexOf('.', 0);
    return r.substring(0, p) + r.substring(p, p + 4);
    }
    //保留整數(shù)同時四入五入
    function changeZeroInt(x) {
    var r = "";
    var v1 = 0;
    r = x.toString();
    var p = r.indexOf('.', 0);
    if (p != -1)
    v1 = r.substring(0, p) * 1;
    else
    v1 = r * 1;
    if (v1 > x)
    return v1;
    else {
    if (p != -1)
    return v1 + 1;
    else
    return v1;
    }
    }