Node之Path模块

path 模块提供了用于处理文件和目录的路径的实用工具
以 E:\foo\bar\index.js 文件为例介绍Path的常用API
首先引入Path模块 const path=require('path')

• __dirname 文件目录绝对路径

__dirname // E:\foo\bar

• __filename 文件绝对路径

__pathname // E:\foo\bar\index.js

• path.join([...paths]) 多参数路径拼接

path.join(__dirname,"..","src") //E:\foo\src
path.join('/bbb/aaa','./test/index.js') //\bbb\aaa\test\index.js

• path.resolve([...paths]) 相对路径转绝对路径，类似于cmd中cd命令，对每一级path都进行cd path处理

path.resolve(__dirname,"../") //E:\foo\src
path.resolve('/bbb/aaa','./test/index.js') //E:\bbb\aaa\test\index.js
path.resolve('/bbb/aaa','test/index.js') //E:\bbb\aaa\test\index.js
path.resolve('/bbb/aaa','/test/index.js') //E:\test\index.js
path.resolve('/bbb/aaa','..','/test/index.js') //E:\bbb\test\index.js

• path.dirname(path) 返回path的目录名

path.dirname(__filename) === __dirname  //true

• path.extname(path) 返回文件的扩展名

path.extname('/foo/bar/baz/asdf/index.html');  //return '.html'
path.extname('/foo/bar/baz/asdf/index.');  //return '.'
path.extname('/foo/bar/baz/asdf/index');  //return ''
path.extname('.index');  //return ''

• path.basename(path[,ext]) 返回path的最后一部分，如果加了扩展名（区分大小写）则是剔除掉扩展名的部分

path.basename('/foo/bar/baz/asdf/index.html');  //return 'index.html'
path.basename('/foo/bar/baz/asdf/index.html','.html');  //return 'index'
path.basename('/foo/bar/baz/asdf/index.HTML','.html');  //return 'index.HTML'

• path.isAbsolute(path) 判断路径是否是绝对路径

path.isAbsolute(".")  //false
path.isAbsolute("/")  //true
path.isAbsolute("./foo/baz")  //false
path.isAbsolute("/foo/baz")  //true