Question

我对nodejs很陌生。我创建了一个函数数组，但无法执行对函数的回调。有人可以帮我吗？

'using strict'

const tasks = [];
tasks.push(function (callback)  {
    console.log('Hi.. executing task 1'); 
    return callback;
});
tasks.push(function (callback) { 
    console.log('Hi.. executing task 2'); 
    return callback; 
});
tasks.push(function (callback) { 
    console.log('Hi.. executing task 3'); 
    return callback; 
});

function iterate(index, callback) {
    if (index === tasks.length) {
        return callback();
    }
    const task = tasks[index];
    task(function () {
        console.log('Hi.. executing task callback'); 
        //the line, I really want to include in here is
        //   iterate(index + 1, callback);
     });
    iterate(index + 1, callback);
}
function finish() {
    console.log('Execution complete');
}
iterate(0, finish);

控制台显示

嗨，..执行任务1

嗨，..执行任务2

嗨，..执行任务3

执行完成

Answer 1

如果您仔细查看它，您将不会执行回调，而只是返回它。所以你可以

import { gql } from "apollo-server-express";

import citySchema from "./city";

const linkSchema = gql`
  type Query {
    _: Boolean
  }

  type Mutation {
    _: Boolean
  }

  type Subscription {
    _: Boolean
  }
`;

export default [linkSchema, citySchema];

或

    cbFunc = task(function () {
        console.log('Hi.. executing task callback'); 
        //the line, I really want to include in here is
        //   iterate(index + 1, callback);
     });
    cbFunc();

为什么不执行数组中的函数回调？

1 个答案: