字符串中的NodeJS v6.9.1变量不起作用

Question

Try to learn basic functions from NodeJS, stuck in append String to file with variable: 尝试从NodeJS学习基本功能，将基本字符串附加到带有变量的文件中：

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

var user = os.userInfo();

fs.appendFile('test.txt', 'Hello ${user.username}!');

From test.txt I got: 从test.txt我得到：

Hello ${user.username}!

What goes wrong here? 这里出什么问题了？

Answer 1

You need to use back-tick (`) instead of ' 您需要使用反勾（`）代替'

fs.appendFile('test.txt', `Hello ${user.username}!`);

Template literals are enclosed by the back-tick (grave accent) character instead of double or single quotes. 模板文字用反引号（重音符号）而不是双引号或单引号引起来。