这在Node.js 10中非常简单:

const Path = require('path');
const FSP = require('fs').promises;

async function copyDir(src,dest) {
    const entries = await FSP.readdir(src, {withFileTypes: true});
    await FSP.mkdir(dest);
    for(let entry of entries) {
        const srcPath = Path.join(src, entry.name);
        const destPath = Path.join(dest, entry.name);
        if(entry.isDirectory()) {
            await copyDir(srcPath, destPath);
        } else {
            await FSP.copyFile(srcPath, destPath);
        }
    }
}

这里假设dest不存在。

下面是一个递归复制目录及其内容到另一个目录的函数:

const fs = require("fs")
const path = require("path")

/**
 * Look ma, it's cp -R.
 * @param {string} src  The path to the thing to copy.
 * @param {string} dest The path to the new copy.
 */
var copyRecursiveSync = function(src, dest) {
  var exists = fs.existsSync(src);
  var stats = exists && fs.statSync(src);
  var isDirectory = exists && stats.isDirectory();
  if (isDirectory) {
    fs.mkdirSync(dest);
    fs.readdirSync(src).forEach(function(childItemName) {
      copyRecursiveSync(path.join(src, childItemName),
                        path.join(dest, childItemName));
    });
  } else {
    fs.copyFileSync(src, dest);
  }
};

目前最上面的答案可以大大简化。

const path = require('path');
const fs = require('fs');

function recursiveCopySync(source, target) {
  if (fs.lstatSync(source).isDirectory()) {
    if (!fs.existsSync(target)) {
      fs.mkdirSync(target);
    }
    let files = fs.readdirSync(source);
    files.forEach((file) => {
      recursiveCopySync(path.join(source, file), path.join(target, file));
    });
  } else {
    if (fs.existsSync(source)) {
      fs.writeFileSync(target, fs.readFileSync(source));
    }
  }
}

我写了这个函数用于在目录之间递归地复制(copyFileSync)或移动(renameSync)文件:

// Copy files
copyDirectoryRecursiveSync(sourceDir, targetDir);
// Move files
copyDirectoryRecursiveSync(sourceDir, targetDir, true);


function copyDirectoryRecursiveSync(source, target, move) {
    if (!fs.lstatSync(source).isDirectory())
        return;

    var operation = move ? fs.renameSync : fs.copyFileSync;
    fs.readdirSync(source).forEach(function (itemName) {
        var sourcePath = path.join(source, itemName);
        var targetPath = path.join(target, itemName);

        if (fs.lstatSync(sourcePath).isDirectory()) {
            fs.mkdirSync(targetPath);
            copyDirectoryRecursiveSync(sourcePath, targetPath);
        }
        else {
            operation(sourcePath, targetPath);
        }
    });
}

如果你在Linux上，性能不是问题，你可以使用child_process模块中的exec函数来执行一个Bash命令:

const { exec } = require('child_process');
exec('cp -r source dest', (error, stdout, stderr) => {...});

在某些情况下，我发现这个解决方案比下载整个模块甚至使用fs模块更简洁。

fs-extra模块工作起来很有魅力。

安装fs-extra:

$ npm install fs-extra

下面是将源目录复制到目标目录的程序。

// Include the fs-extra package
var fs = require("fs-extra");

var source = 'folderA'
var destination = 'folderB'

// Copy the source folder to the destination
fs.copy(source, destination, function (err) {
    if (err){
        console.log('An error occurred while copying the folder.')
        return console.error(err)
    }
    console.log('Copy completed!')
});

参考文献

fs-extra: https://www.npmjs.com/package/fs-extra

示例:Node.js教程- Node.js复制文件夹