js取小数点后两位四种方法

// 1.通过substring截取。function getnum() {var num = 22.123456;var s = num.toString();var result = s.substring(0,s.indexOf(".")+3);var result2 = s.substring(0,s.indexOf(".")+5);console.log(result);console.

琪公子呀

19280人浏览 · 2022-02-23 16:18:41

琪公子呀 · 2022-02-23 16:18:41 发布

// 1.通过substring截取。
function getnum() {
    var num = 22.123456;
    var s = num.toString();
    var result = s.substring(0,s.indexOf(".")+3);
    var result2 = s.substring(0,s.indexOf(".")+5);
    console.log(result);
    console.log(result2);
}
getnum();

// 2. 正则表达式。
function getnum() {
    var num = 22.123456;
    var aNew;
    var re = /([0-9]+\.[0-9]{4})[0-9]*/;
    aNew = num.toString().replace(re,"$1");
    alert(aNew);
}
getnum();

// 3.数据类型保留上。
function getnum() {
    var num=22.123456;
    console.log( Math.round(num*10000)/10000);
    console.log( Math.round(num*1000)/1000);
    console.log( Math.round(num*100)/100);
    console.log( Math.round(num*10)/10);
}
getnum();

// 4.toFixed方法
let num = 22.123456;
alert(num.toFixed(4));