Node.js（三）Lodash

npm init -y(初始化项目)

npm i --save lodash（引入lodash）

const _=require("lodash");

let stus=[

    {id:1,name:"tom",age:40},

    {id:2,name:"xiao",age:28},

    {id:3,name:"gien",age:11},

    {id:4,name:"ovber",age:16},

    {id:5,name:"have",age:26},

];

//first输出第一个元素

let f1=_.first([1,2,3]);

console.log(f1);

let f2=_.first(stus).age;

console.log(f2);

//last输出最后一个元素

let f3=_.last([1,2,3]);

console.log(f3);

let f4=_.last(stus).age;

console.log(f4);

//findIndex查找元素的索引

let f5=_.findIndex(stus,o=>o.name==="have");

console.log(f5);

//find查找元素(只查找第一个)拿到数据

let f6=_.find(stus,o=>o.name.indexOf("o")>0);

console.log(f6);

//orderBy排序

let f9=_.orderBy(stus,["age"],["desc"]);

console.log(f9);

//sampleSize随机数

let sampleSize=_.sampleSize([1,2,3,4,5,6,7,8,9,10], 3);

console.log(sampleSize);

//size返回长度

let size=_.size([1,2,3,4,5,6,7]);

console.log(size);

//round四舍五入

let round=_.round(4.06, 2);

console.log(round);

//sum计算总和

let sum=_.sum([1,2,3,4,5,6,7,8,9,10]);

console.log(sum);

//differenceWith过滤元素

let List=[{'a':1,'b':2,'c':3,'d':'4','e':5},{'a':100,'b':99,'c':520}]

let differenceWith=_.differenceWith(List,[{'a':1,'b':2,'c':3,'d':'4','e':5}], _.isEqual);

console.log(differenceWith);

Node.js（三）Lodash的相关教程结束。