Node.js 错误MongooseServerSelectionError:connect-EconResured 127.0.0.1:27017

每当我试图从mongoose连接到我的mongo服务器时，就会出现这个错误。 我已经安装了MongoDB，并且正在使用命令mongod运行我的服务器，我可以与MongoShell交互并使用那里的所有命令

我之前曾尝试使用mongoose连接到此端口，但该端口正常工作。我还尝试使用不同的端口号删除数据库文件并重新创建它。但仍然是相同的错误日志

尽管如此，我也安装了猫鼬，npm工作正常

错误日志

    MongooseServerSelectionError: connect ECONNREFUSED 127.0.0.1:27017
    at NativeConnection.Connection.openUri (/mnt/d/Source code/Web_dev/mongooseBasics/test/node_modules/mongoose/lib/connection.js:846:32)
    at /mnt/d/Source code/Web_dev/mongooseBasics/test/node_modules/mongoose/lib/index.js:350:10
    at /mnt/d/Source code/Web_dev/mongooseBasics/test/node_modules/mongoose/lib/helpers/promiseOrCallback.js:31:5
    at new Promise (<anonymous>)
    at promiseOrCallback (/mnt/d/Source code/Web_dev/mongooseBasics/test/node_modules/mongoose/lib/helpers/promiseOrCallback.js:30:10)
    at Mongoose._promiseOrCallback (/mnt/d/Source code/Web_dev/mongooseBasics/test/node_modules/mongoose/lib/index.js:1154:10)
    at Mongoose.connect (/mnt/d/Source code/Web_dev/mongooseBasics/test/node_modules/mongoose/lib/index.js:349:20)
    at Object.<anonymous> (/mnt/d/Source code/Web_dev/mongooseBasics/test/index.js:2:10)
    at Module._compile (internal/modules/cjs/loader.js:1063:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
    at Module.load (internal/modules/cjs/loader.js:928:32)
    at Function.Module._load (internal/modules/cjs/loader.js:769:14)
    at Function.executeUserEntryPoint [as runMain] (internal/modules/run_main.js:72:12)
    at internal/main/run_main_module.js:17:47 {
  reason: TopologyDescription {
    type: 'Single',
    setName: null,
    maxSetVersion: null,
    maxElectionId: null,
    servers: Map(1) { 'localhost:27017' => [ServerDescription] },
    stale: false,
    compatible: true,
    compatibilityError: null,
    logicalSessionTimeoutMinutes: null,
    heartbeatFrequencyMS: 10000,
    localThresholdMS: 15,
    commonWireVersion: null
  }
}

---

“ECONNREFUSED”表示操作系统主动拒绝连接，因为该端口上没有任何内容正在侦听。

const mongoose = require('mongoose');
mongoose.connect('mongodb://localhost:27017/test', {useNewUrlParser: true, useUnifiedTopology: true})
    .then(() => {
        console.log("Connected");
    })
    .catch(err => {
        console.log('Error');
        console.log(err);
    })