javascript - 将 ES6 类方法作为要在函数内部调用的函数参数传递

Question

如何修复下面的代码，以便能够使用 call 调用类方法。

类定义:

class User {
   constructor(..) {...}
   async method(start, end) {}
}

尝试将类方法作为函数参数传递:

const User = require('./user'); 

async function getData(req, res) {
  // User.method is undefined, since User refers to User constructor
  await get(req, res, User.method); 
}

async function get(req, res, f) {
  let start = ...;
  let end = ...;
  let params = ...;
  let user = new User(params);
  // f is undefined here
  let stream = await f.call(user, start, end); 
}

Answer 1

User method is undefined, since User refers to constructor

你正在寻找User.prototype.method:

async function getData(req, res) {
    await get(req, res, User.prototype.method); 
}

请记住，ES6 类是语言原型(prototype)性质之上的语法糖。