javascript - 如何在Node.js中定义对象

Question

我正在尝试为对象分配一个值，但是当我尝试显示它时，它总是返回[]。这是我的一段代码

const exspress = require("express");
const aplication = exspress();
//body parser for informaton monggo
const bodyparser = require("body-parser");
//configuration for node aplication
aplication.use(
  bodyparser.urlencoded({
    extended: false
  })
);
const mongose = require("mongoose");

const router = exspress.Router();

const PingModel = mongose.model("Ping");

const ping = require("ping");
var tcpp = require("tcp-ping");     
var obj = Array();
        var a = 0;
        var b = pingtime;
        for(a; a<b; a++){
        ping.promise.probe(host).then(function(data) {
            const storePing = new PingModel();
            storePing.hostPing = host;
            storePing.hostIp = data.numeric_host;
            if (data.alive) {
              storePing.hostStatus = "Ok";
            } else {
              storePing.hostStatus = "Not_ok";
            }
            if (data.alive) {
              storePing.hostLatency = "true";
            } else {
              storePing.hostLatency = "false";
            }
            storePing.save();
            window.obj = storePing
            // return this.obj[a] = storePing;
          });
          console.log(obj);
        }
 module.exports = router;

你们能告诉我如何定义一个对象并用我在单独的代码/函数中使用它的数据/值填充它吗？

Answer 1

尝试更改window.obj至obj作为您的obj只是一个变量，它不在 window 上对象

此外，在声明对象时，您已将其声明为数组。如果你想要一个对象，你可以使用 var obj = {}; ，尽管如此，我们还是用 storePing 重新分配它

此外，您还需要移动您的 console.log进入then promise 的回调，因为它是您拥有的异步代码 - 目前，您的 console.log将在 then 之前触发 promise 的回调已执行，因此 obj还没有达到您期望的值

一些很长的东西 -

const router = exspress.Router();

const PingModel = mongose.model("Ping");

const ping = require("ping");
var tcpp = require("tcp-ping");     
var obj = {}; // NOTE, object instead of array, though this gets reassigned anyway, so doesn't really matter
        var a = 0;
        var b = pingtime;
        for(a; a<b; a++){
        ping.promise.probe(host).then(function(data) {
            const storePing = new PingModel();
            storePing.hostPing = host;
            storePing.hostIp = data.numeric_host;
            if (data.alive) {
              storePing.hostStatus = "Ok";
            } else {
              storePing.hostStatus = "Not_ok";
            }
            if (data.alive) {
              storePing.hostLatency = "true";
            } else {
              storePing.hostLatency = "false";
            }
            storePing.save();
            obj = storePing // <-- NOTE, no window object

            console.log(obj); // <-- NOTE, logging inside the then callback
            // return this.obj[a] = storePing;
          });
        }
 module.exports = router;