ES6（数值扩展）

{

    //二进制
    console.log(0b111110111);//503
    //八进制
    console.log(0o767);//503
}

//判断数值是否有尽
{
    console.log('15', Number.isFinite(15));//true
    console.log('NaN', Number.isFinite(NaN));//false
    console.log('1/0', Number.isFinite('true' / 0));//false

    console.log('NaN', Number.isNaN(NaN));//true
    console.log('0', Number.isNaN(0));//false
}

//判断数值是否是整数
{
    console.log('25', Number.isInteger(25));//true
    console.log('25.0', Number.isInteger(25.0));//true
    console.log('25.1 ', Number.isInteger(25.1));//false
    console.log('22 ', Number.isInteger('22'));//false
    console.log('abc ', Number.isInteger('abc'));//false
}

//判断数值是否在有效值范围
{
    console.log(Number.MAX_SAFE_INTEGER, Number.MIN_SAFE_INTEGER);
    console.log('10', Number.isSafeInteger(10));//true
    console.log('a', Number.isSafeInteger('a'));//false
}

//取整
{
    console.log('4.1', Math.trunc(4.1));//4
    console.log('4.6', Math.trunc(4.6));//4
    console.log('4.9', Math.trunc(4.9));//4
}

//判断数值为正数、负数还是零
{
    console.log('-5', Math.sign(-5));//-1 负数
    console.log('0', Math.sign(0));//0 零
    console.log('4', Math.sign(4));//1 正数
    console.log('50', Math.sign('50'));//1 正数
    console.log('abc', Math.sign('abc'));//NaN
}

//立方根
{
    console.log('-1', Math.cbrt(-1));//-1
    console.log('8', Math.cbrt(8));//2
}