我就废话不多说了，大家还是直接看代码吧~demo.js：
//path模块
var path=require('path'); /*nodejs自带的模块*/
var extname=path.extname("123.html"); //获取文件的后缀名
console.log(extname);
//path模块
var path=require('path'); /*nodejs自带的模块*/
var extname=path.extname("123.html"); //获取文件的后缀名
console.log(extname);补充知识：node 的path模块中 path.resolve()和path.join()的区别补充知识：补充知识：node 的path模块中 path.resolve()和path.join()的区别一、path模块的引入。一、path模块的引入。直接引用。node中自带的模块
const path = require('path');
const path = require('path');
二、path.join(path1，path2，path3.......)二、path.join(path1，path2，path3.......)作用：将路径片段使用特定的分隔符（window：\）连接起来形成路径，并规范化生成的路径。若任意一个路径片段类型错误，会报错。
const path = require('path');
let myPath = path.join(__dirname,'/img/so');
let myPath2 = path.join(__dirname,'./img/so');
let myPath3=path.join('/foo', 'bar', 'baz/asdf', 'quux', '..');

console.log(__dirname);

console.log(myPath);

console.log(myPath2);

console.log(myPath3);
const path = require('path');
let myPath = path.join(__dirname,'/img/so');
let myPath2 = path.join(__dirname,'./img/so');
let myPath3=path.join('/foo', 'bar', 'baz/asdf', 'quux', '..');

console.log(__dirname);

console.log(myPath);

console.log(myPath2);

console.log(myPath3); 三、path.resolve([from...],to)三、path.resolve([from...],to)作用：把一个路径或路径片段的序列解析为一个绝对路径。相当于执行cd操作。/被解析为根目录。
let myPath = path.resolve(__dirname,'/img/so');
let myPath2 = path.resolve(__dirname,'./img/so');
let myPath3=path.resolve('/foo/bar', './baz');
let myPath4=path.resolve('/foo/bar', '/tmp/file/');

console.log(__dirname);

console.log(myPath);

console.log(myPath2);

console.log(myPath3);
console.log(myPath4);
let myPath = path.resolve(__dirname,'/img/so');
let myPath2 = path.resolve(__dirname,'./img/so');
let myPath3=path.resolve('/foo/bar', './baz');
let myPath4=path.resolve('/foo/bar', '/tmp/file/');

console.log(__dirname);

console.log(myPath);

console.log(myPath2);

console.log(myPath3);
console.log(myPath4); 以上这篇Node.js path模块,获取文件后缀名操作就是小编分享给大家的全部内容了，希望能给大家一个参考。