• Node.js path All In One


    Node.js path All In One

    const path = require('path');
    const app = '/users/github/xgqfrms/app.ts';
    
    const dirname = path.dirname(app);
    const basename = path.basename(app);
    const extname = path.extname(app);
    
    const log = console.log;
    
    log('__dirname =', __dirname);
    
    log('basename =', basename);
    log('extname =', extname);
    log('dirname =', dirname);
    
    /*
    
    __dirname = /Users/xgqfrms-mbp/Documents/GitHub/demo/src
    dirname = /users/github/xgqfrms
    basename = app.ts
    extname = .ts
    
    */
    
    
    $ node ./src/app.js
    
    

    https://nodejs.dev/learn/nodejs-file-paths

    path.parse() & path.format()

    root: the root
    dir: the folder path starting from the root
    base: the file name + extension
    name: the file name
    ext: the file extension

    
    const path = require('path');
    
    path.parse('/users/test.txt');
    
    /*
    {
      root: '/',
      dir: '/users',
      base: 'test.txt',
      ext: '.txt',
      name: 'test'
    }
    */
    
    

    root: the root
    dir: the folder path starting from the root
    base: the file name + extension
    name: the file name
    ext: the file extension

    const path = require('path');
    
    const appRoot = '/users/xgqfrms/';
    const appDir = '/users/xgqfrms/github';
    const appBase = 'app.ts';
    const appName = 'app';
    const appExtension = '.ts';
    
    // POSIX
    const filename = path.format({
      dir: appDir,
      base: appBase,
    });
    
    const filename2 = path.format({
      root: appRoot,
      name: appName,
      ext: appExtension,
    });
    
    // Windows 磁盘分区 C:
    const filename3 = path.format({
      dir: 'C:\\Users\\xgqfrms\\github',
      base: 'app.ts',
    });
    
    const log = console.log;
    
    // log('__dirname =', __dirname);
    
    log('filename =', filename);
    log('filename2 =', filename2);
    log('filename3 =', filename3);
    
    /*
    
    filename = /users/xgqfrms/github/app.ts
    filename2 = /users/xgqfrms/app.ts
    filename3 = C:\Users\xgqfrms\github/app.ts
    
    */
    
    
    
    $ node ./src/fromat.js
    
    

    https://nodejs.dev/learn/the-nodejs-path-module

    ES5

    // commonjs
    const path = require('path')
    
    
    

    ES6

    // esm
    import path form 'path';
    
    
    

    demo

    CJS

    var fs = require("fs");
    var path = require("path");
    
    const log = console.log;
    console.log('commonjs __dirname =', __dirname);
    // commonjs __dirname = /Users/xgqfrms-mbp/Documents/GitHub/app/src
    
    // / 当前文件路径下创建文件夹 ✅  (./src => ./src/upload)
    // const dir = __dirname + '/upload';
    // console.log('commonjs dir =', dir);
    // commonjs dir = /Users/xgqfrms-mbp/Documents/GitHub/app/src/upload
    
    // ../ 当前文件上一层路径下创建文件夹 ❌ (./src => ./upload)
    // const dir = __dirname + '../upload';
    // console.log('commonjs dir =', dir);
    // Error: ENOENT: no such file or directory, mkdir '/Users/xgqfrms-mbp/Documents/GitHub/app/src../upload'
    
    // ../ 当前文件上一层路径下创建文件夹 ✅  (./src => ./upload)
    // const dir = path.resolve('../upload');
    const dir = path.resolve(__dirname, '../upload');
    console.log('commonjs dir =', dir);
    // commonjs dir = /Users/xgqfrms-mbp/Documents/GitHub/app/upload
    
    
    if (!fs.existsSync(dir)) {
      fs.mkdirSync(dir);
    }
    
    // if (!fs.existsSync(dir)) {
    //   fs.mkdirSync(dir, {
    //     mode: 0o744,
    //   });
    //   // mode's default value is 0o744
    // }
    
    
    // if (!fs.existsSync(dir)) {
    //   fs.mkdirSync(dir, {
    //     recursive: true,
    //     mode: 0o744,
    //   });
    //   // mode's default value is 0o744
    // }
    
    
    /*
    
    // mjs
    node --experimental-modules ./src/mkdir.mjs
    
    # "type": "module",
    node ./src/mkdir.js
    
    node ./src/mkdir.cjs
    
    */
    
    

    ESM

    import fs from "fs";
    import path from "path";
    
    
    const log = console.log;
    
    // 指定当前 root 路径 ✅
    const __dirname = path.resolve('./src');
    
    console.log('esm __dirname =', __dirname);
    // esm __dirname = /Users/xgqfrms-mbp/Documents/GitHub/app
    
    // ../ 当前文件上一层路径下创建文件夹 ✅  (./src => ./upload)
    const dir = path.resolve(__dirname, '../upload');
    log('esm dir =', dir);
    // esm dir = /Users/xgqfrms-mbp/Documents/GitHub/app/upload
    
    // ../ 当前文件上一层路径下创建文件夹 ❌  (./src => ./upload)
    // const dir = __dirname + '../upload';
    // log('esm dir =', dir);
    // Error: ENOENT: no such file or directory, mkdir '/Users/xgqfrms-mbp/Documents/GitHub/app/src../upload'
    
    if (!fs.existsSync(dir)) {
      fs.mkdirSync(dir);
    }
    
    // if (!fs.existsSync(dir)) {
    //   fs.mkdirSync(dir, {
    //     mode: 0o744,
    //   });
    //   // mode's default value is 0o744
    // }
    
    // if (!fs.existsSync(dir)) {
    //   fs.mkdirSync(dir, {
    //     recursive: true,
    //     mode: 0o744,
    //   });
    //   // mode's default value is 0o744
    // }
    
    
    /*
    
    node --experimental-modules ./src/mkdir-src.mjs
    
    node ./src/mkdir-src.js
    
    */
    
    

    refs

    https://nodejs.org/api/path.html



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  • 原文地址:https://www.cnblogs.com/xgqfrms/p/16155641.html
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