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Post引數為空NodeJSExpress

2021-12-07 00:36:16 後端開發

我剛剛在 NodeJS 中設定了一個專案，我正在嘗試從我的前端（通過 API）執行 POST 請求。一切正常，發布請求成功執行，所有引數都已發送，我的 NodeJS 應用程式收到請求，但正文/引數為空。

這是我正在使用的代碼：

const http = require('http');
const express = require('express');
const cors = require('cors');
const bodyParser = require('body-parser');

const hostname = '127.0.0.1';
const port = 3000;
const app = express();


const corsOptions = {
  origin: 'http://localhost:4200',
  allowedHeaders: ['Content-Type']
}


app.options('*', cors(corsOptions));
app.use(cors(corsOptions));
app.use(bodyParser.urlencoded({extended : true}));
app.use(bodyParser.json());

app.post('/', function (req, res) {
  console.log(req);
  res.send('Hello World!');
})

當我發布到默認路徑時，應用程式顯示“Hello World”，并且還顯示所有req資訊，但引數為空{}

這是我的客戶端代碼：

  testPost(parameter1: any, parameter2: any): Observable<any> {
    return this.http.post(URL_API.url,
                                {'parameter1': parameter1, 'parameter2': parameter2},
                                {headers: new HttpHeaders({'Content-Type': '*'})});
  }

這是我在 NodeJS 中得到的：

<ref *2> IncomingMessage {
  _readableState: ReadableState {
    objectMode: false,
    highWaterMark: 16384,
    buffer: BufferList { head: null, tail: null, length: 0 },
    length: 0,
    pipes: [],
    flowing: null,
    ended: false,
    endEmitted: false,
    reading: false,
    sync: true,
    needReadable: false,
    emittedReadable: false,
    readableListening: false,
    resumeScheduled: false,
    errorEmitted: false,
    emitClose: true,
    autoDestroy: false,
    destroyed: false,
    errored: null,
    closed: false,
    closeEmitted: false,
    defaultEncoding: 'utf8',
    awaitDrainWriters: null,
    multiAwaitDrain: false,
    readingMore: true,
    decoder: null,
    encoding: null,
    [Symbol(kPaused)]: null
  },
  _events: [Object: null prototype] { end: [Function: clearRequestTimeout] },
  _eventsCount: 1,
  _maxListeners: undefined,
  socket: <ref *1> Socket {
    connecting: false,
    _hadError: false,
    _parent: null,
    _host: null,
    _readableState: ReadableState {
      objectMode: false,
      highWaterMark: 16384,
      buffer: BufferList { head: null, tail: null, length: 0 },
      length: 0,
      pipes: [],
      flowing: true,
      ended: false,
      endEmitted: false,
      reading: true,
      sync: false,
      needReadable: true,
      emittedReadable: false,
      readableListening: false,
      resumeScheduled: false,
      errorEmitted: false,
      emitClose: false,
      autoDestroy: false,
      destroyed: false,
      errored: null,
      closed: false,
      closeEmitted: false,
      defaultEncoding: 'utf8',
      awaitDrainWriters: null,
      multiAwaitDrain: false,
      readingMore: false,
      decoder: null,
      encoding: null,
      [Symbol(kPaused)]: false
    },
    _events: [Object: null prototype] {
      end: [Array],
      timeout: [Function: socketOnTimeout],
      data: [Function: bound socketOnData],
      error: [Function: socketOnError],
      close: [Array],
      drain: [Function: bound socketOnDrain],
      resume: [Function: onSocketResume],
      pause: [Function: onSocketPause]
    },
    _eventsCount: 8,
    _maxListeners: undefined,
    _writableState: WritableState {
      objectMode: false,
      highWaterMark: 16384,
      finalCalled: false,
      needDrain: false,
      ending: false,
      ended: false,
      finished: false,
      destroyed: false,
      decodeStrings: false,
      defaultEncoding: 'utf8',
      length: 0,
      writing: false,
      corked: 0,
      sync: false,
      bufferProcessing: false,
      onwrite: [Function: bound onwrite],
      writecb: null,
      writelen: 0,
      afterWriteTickInfo: null,
      buffered: [],
      bufferedIndex: 0,
      allBuffers: true,
      allNoop: true,
      pendingcb: 0,
      prefinished: false,
      errorEmitted: false,
      emitClose: false,
      autoDestroy: false,
      errored: null,
      closed: false,
      closeEmitted: false
    },
    allowHalfOpen: true,
    _sockname: null,
    _pendingData: null,
    _pendingEncoding: '',
    server: Server {
      maxHeaderSize: undefined,
      insecureHTTPParser: undefined,
      _events: [Object: null prototype],
      _eventsCount: 2,
      _maxListeners: undefined,
      _connections: 1,
      _handle: [TCP],
      _usingWorkers: false,
      _workers: [],
      _unref: false,
      allowHalfOpen: true,
      pauseOnConnect: false,
      httpAllowHalfOpen: false,
      timeout: 0,
      keepAliveTimeout: 5000,
      maxHeadersCount: null,
      headersTimeout: 60000,
      requestTimeout: 0,
      _connectionKey: '4:127.0.0.1:3000',
      [Symbol(IncomingMessage)]: [Function: IncomingMessage],
      [Symbol(ServerResponse)]: [Function: ServerResponse],
      [Symbol(kCapture)]: false,
      [Symbol(async_id_symbol)]: 11
    },
    _server: Server {
      maxHeaderSize: undefined,
      insecureHTTPParser: undefined,
      _events: [Object: null prototype],
      _eventsCount: 2,
      _maxListeners: undefined,
      _connections: 1,
      _handle: [TCP],
      _usingWorkers: false,
      _workers: [],
      _unref: false,
      allowHalfOpen: true,
      pauseOnConnect: false,
      httpAllowHalfOpen: false,
      timeout: 0,
      keepAliveTimeout: 5000,
      maxHeadersCount: null,
      headersTimeout: 60000,
      requestTimeout: 0,
      _connectionKey: '4:127.0.0.1:3000',
      [Symbol(IncomingMessage)]: [Function: IncomingMessage],
      [Symbol(ServerResponse)]: [Function: ServerResponse],
      [Symbol(kCapture)]: false,
      [Symbol(async_id_symbol)]: 11
    },
    parser: HTTPParser {
      '0': [Function: bound setRequestTimeout],
      '1': [Function: parserOnHeaders],
      '2': [Function: parserOnHeadersComplete],
      '3': [Function: parserOnBody],
      '4': [Function: parserOnMessageComplete],
      '5': [Function: bound onParserExecute],
      '6': [Function: bound onParserTimeout],
      _headers: [],
      _url: '',
      socket: [Circular *1],
      incoming: [Circular *2],
      outgoing: null,
      maxHeaderPairs: 2000,
      _consumed: true,
      onIncoming: [Function: bound parserOnIncoming],
      [Symbol(resource_symbol)]: [HTTPServerAsyncResource]
    },
    on: [Function: socketListenerWrap],
    addListener: [Function: socketListenerWrap],
    prependListener: [Function: socketListenerWrap],
    _paused: false,
    _httpMessage: ServerResponse {
      _events: [Object: null prototype],
      _eventsCount: 1,
      _maxListeners: undefined,
      outputData: [],
      outputSize: 0,
      writable: true,
      destroyed: false,
      _last: false,
      chunkedEncoding: false,
      shouldKeepAlive: true,
      _defaultKeepAlive: true,
      useChunkedEncodingByDefault: true,
      sendDate: true,
      _removedConnection: false,
      _removedContLen: false,
      _removedTE: false,
      _contentLength: null,
      _hasBody: true,
      _trailer: '',
      finished: false,
      _headerSent: false,
      socket: [Circular *1],
      _header: null,
      _keepAliveTimeout: 5000,
      _onPendingData: [Function: bound updateOutgoingData],
      _sent100: false,
      _expect_continue: false,
      req: [Circular *2],
      locals: [Object: null prototype] {},
      [Symbol(kCapture)]: false,
      [Symbol(kNeedDrain)]: false,
      [Symbol(corked)]: 0,
      [Symbol(kOutHeaders)]: [Object: null prototype]
    },
    timeout: 0,
    [Symbol(async_id_symbol)]: 20,
    [Symbol(kHandle)]: TCP {
      reading: true,
      onconnection: null,
      _consumed: true,
      [Symbol(owner_symbol)]: [Circular *1]
    },
    [Symbol(kSetNoDelay)]: false,
    [Symbol(lastWriteQueueSize)]: 0,
    [Symbol(timeout)]: Timeout {
      _idleTimeout: -1,
      _idlePrev: null,
      _idleNext: null,
      _idleStart: 2049,
      _onTimeout: null,
      _timerArgs: undefined,
      _repeat: null,
      _destroyed: true,
      [Symbol(refed)]: false,
      [Symbol(kHasPrimitive)]: false,
      [Symbol(asyncId)]: 28,
      [Symbol(triggerId)]: 24
    },
    [Symbol(kBuffer)]: null,
    [Symbol(kBufferCb)]: null,
    [Symbol(kBufferGen)]: null,
    [Symbol(kCapture)]: false,
    [Symbol(kBytesRead)]: 0,
    [Symbol(kBytesWritten)]: 0,
    [Symbol(RequestTimeout)]: undefined
  },
  httpVersionMajor: 1,
  httpVersionMinor: 1,
  httpVersion: '1.1',
  complete: false,
  headers: {
    host: '127.0.0.1:3000',
    connection: 'keep-alive',
    'content-length': '66',
    'sec-ch-ua': '"Google Chrome";v="95", "Chromium";v="95", ";Not A Brand";v="99"',
    accept: 'application/json, text/plain, */*',
    'content-type': 'applcation/json',
    'sec-ch-ua-mobile': '?0',
    'user-agent': 'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.69 Safari/537.36',
    'sec-ch-ua-platform': '"Linux"',
    origin: 'http://localhost:4200',
    'sec-fetch-site': 'cross-site',
    'sec-fetch-mode': 'cors',
    'sec-fetch-dest': 'empty',
    referer: 'http://localhost:4200/',
    'accept-encoding': 'gzip, deflate, br',
    'accept-language': 'en-US,en;q=0.9'
  },
  rawHeaders: [
    'Host',
    '127.0.0.1:3000',
    'Connection',
    'keep-alive',
    'Content-Length',
    '66',
    'sec-ch-ua',
    '"Google Chrome";v="95", "Chromium";v="95", ";Not A Brand";v="99"',
    'Accept',
    'application/json, text/plain, */*',
    'Content-Type',
    'applcation/json',
    'sec-ch-ua-mobile',
    '?0',
    'User-Agent',
    'Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.69 Safari/537.36',
    'sec-ch-ua-platform',
    '"Linux"',
    'Origin',
    'http://localhost:4200',
    'Sec-Fetch-Site',
    'cross-site',
    'Sec-Fetch-Mode',
    'cors',
    'Sec-Fetch-Dest',
    'empty',
    'Referer',
    'http://localhost:4200/',
    'Accept-Encoding',
    'gzip, deflate, br',
    'Accept-Language',
    'en-US,en;q=0.9'
  ],
  trailers: {},
  rawTrailers: [],
  aborted: false,
  upgrade: false,
  url: '/',
  method: 'POST',
  statusCode: null,
  statusMessage: null,
  client: <ref *1> Socket {
    connecting: false,
    _hadError: false,
    _parent: null,
    _host: null,
    _readableState: ReadableState {
      objectMode: false,
      highWaterMark: 16384,
      buffer: BufferList { head: null, tail: null, length: 0 },
      length: 0,
      pipes: [],
      flowing: true,
      ended: false,
      endEmitted: false,
      reading: true,
      sync: false,
      needReadable: true,
      emittedReadable: false,
      readableListening: false,
      resumeScheduled: false,
      errorEmitted: false,
      emitClose: false,
      autoDestroy: false,
      destroyed: false,
      errored: null,
      closed: false,
      closeEmitted: false,
      defaultEncoding: 'utf8',
      awaitDrainWriters: null,
      multiAwaitDrain: false,
      readingMore: false,
      decoder: null,
      encoding: null,
      [Symbol(kPaused)]: false
    },
    _events: [Object: null prototype] {
      end: [Array],
      timeout: [Function: socketOnTimeout],
      data: [Function: bound socketOnData],
      error: [Function: socketOnError],
      close: [Array],
      drain: [Function: bound socketOnDrain],
      resume: [Function: onSocketResume],
      pause: [Function: onSocketPause]
    },
    _eventsCount: 8,
    _maxListeners: undefined,
    _writableState: WritableState {
      objectMode: false,
      highWaterMark: 16384,
      finalCalled: false,
      needDrain: false,
      ending: false,
      ended: false,
      finished: false,
      destroyed: false,
      decodeStrings: false,
      defaultEncoding: 'utf8',
      length: 0,
      writing: false,
      corked: 0,
      sync: false,
      bufferProcessing: false,
      onwrite: [Function: bound onwrite],
      writecb: null,
      writelen: 0,
      afterWriteTickInfo: null,
      buffered: [],
      bufferedIndex: 0,
      allBuffers: true,
      allNoop: true,
      pendingcb: 0,
      prefinished: false,
      errorEmitted: false,
      emitClose: false,
      autoDestroy: false,
      errored: null,
      closed: false,
      closeEmitted: false
    },
    allowHalfOpen: true,
    _sockname: null,
    _pendingData: null,
    _pendingEncoding: '',
    server: Server {
      maxHeaderSize: undefined,
      insecureHTTPParser: undefined,
      _events: [Object: null prototype],
      _eventsCount: 2,
      _maxListeners: undefined,
      _connections: 1,
      _handle: [TCP],
      _usingWorkers: false,
      _workers: [],
      _unref: false,
      allowHalfOpen: true,
      pauseOnConnect: false,
      httpAllowHalfOpen: false,
      timeout: 0,
      keepAliveTimeout: 5000,
      maxHeadersCount: null,
      headersTimeout: 60000,
      requestTimeout: 0,
      _connectionKey: '4:127.0.0.1:3000',
      [Symbol(IncomingMessage)]: [Function: IncomingMessage],
      [Symbol(ServerResponse)]: [Function: ServerResponse],
      [Symbol(kCapture)]: false,
      [Symbol(async_id_symbol)]: 11
    },
    _server: Server {
      maxHeaderSize: undefined,
      insecureHTTPParser: undefined,
      _events: [Object: null prototype],
      _eventsCount: 2,
      _maxListeners: undefined,
      _connections: 1,
      _handle: [TCP],
      _usingWorkers: false,
      _workers: [],
      _unref: false,
      allowHalfOpen: true,
      pauseOnConnect: false,
      httpAllowHalfOpen: false,
      timeout: 0,
      keepAliveTimeout: 5000,
      maxHeadersCount: null,
      headersTimeout: 60000,
      requestTimeout: 0,
      _connectionKey: '4:127.0.0.1:3000',
      [Symbol(IncomingMessage)]: [Function: IncomingMessage],
      [Symbol(ServerResponse)]: [Function: ServerResponse],
      [Symbol(kCapture)]: false,
      [Symbol(async_id_symbol)]: 11
    },
    parser: HTTPParser {
      '0': [Function: bound setRequestTimeout],
      '1': [Function: parserOnHeaders],
      '2': [Function: parserOnHeadersComplete],
      '3': [Function: parserOnBody],
      '4': [Function: parserOnMessageComplete],
      '5': [Function: bound onParserExecute],
      '6': [Function: bound onParserTimeout],
      _headers: [],
      _url: '',
      socket: [Circular *1],
      incoming: [Circular *2],
      outgoing: null,
      maxHeaderPairs: 2000,
      _consumed: true,
      onIncoming: [Function: bound parserOnIncoming],
      [Symbol(resource_symbol)]: [HTTPServerAsyncResource]
    },
    on: [Function: socketListenerWrap],
    addListener: [Function: socketListenerWrap],
    prependListener: [Function: socketListenerWrap],
    _paused: false,
    _httpMessage: ServerResponse {
      _events: [Object: null prototype],
      _eventsCount: 1,
      _maxListeners: undefined,
      outputData: [],
      outputSize: 0,
      writable: true,
      destroyed: false,
      _last: false,
      chunkedEncoding: false,
      shouldKeepAlive: true,
      _defaultKeepAlive: true,
      useChunkedEncodingByDefault: true,
      sendDate: true,
      _removedConnection: false,
      _removedContLen: false,
      _removedTE: false,
      _contentLength: null,
      _hasBody: true,
      _trailer: '',
      finished: false,
      _headerSent: false,
      socket: [Circular *1],
      _header: null,
      _keepAliveTimeout: 5000,
      _onPendingData: [Function: bound updateOutgoingData],
      _sent100: false,
      _expect_continue: false,
      req: [Circular *2],
      locals: [Object: null prototype] {},
      [Symbol(kCapture)]: false,
      [Symbol(kNeedDrain)]: false,
      [Symbol(corked)]: 0,
      [Symbol(kOutHeaders)]: [Object: null prototype]
    },
    timeout: 0,
    [Symbol(async_id_symbol)]: 20,
    [Symbol(kHandle)]: TCP {
      reading: true,
      onconnection: null,
      _consumed: true,
      [Symbol(owner_symbol)]: [Circular *1]
    },
    [Symbol(kSetNoDelay)]: false,
    [Symbol(lastWriteQueueSize)]: 0,
    [Symbol(timeout)]: Timeout {
      _idleTimeout: -1,
      _idlePrev: null,
      _idleNext: null,
      _idleStart: 2049,
      _onTimeout: null,
      _timerArgs: undefined,
      _repeat: null,
      _destroyed: true,
      [Symbol(refed)]: false,
      [Symbol(kHasPrimitive)]: false,
      [Symbol(asyncId)]: 28,
      [Symbol(triggerId)]: 24
    },
    [Symbol(kBuffer)]: null,
    [Symbol(kBufferCb)]: null,
    [Symbol(kBufferGen)]: null,
    [Symbol(kCapture)]: false,
    [Symbol(kBytesRead)]: 0,
    [Symbol(kBytesWritten)]: 0,
    [Symbol(RequestTimeout)]: undefined
  },
  _consuming: false,
  _dumped: false,
  next: [Function: next],
  baseUrl: '',
  originalUrl: '/',
  _parsedUrl: Url {
    protocol: null,
    slashes: null,
    auth: null,
    host: null,
    port: null,
    hostname: null,
    hash: null,
    search: null,
    query: null,
    pathname: '/',
    path: '/',
    href: '/',
    _raw: '/'
  },
  params: {},
  query: {},
  res: <ref *3> ServerResponse {
    _events: [Object: null prototype] { finish: [Function: bound resOnFinish] },
    _eventsCount: 1,
    _maxListeners: undefined,
    outputData: [],
    outputSize: 0,
    writable: true,
    destroyed: false,
    _last: false,
    chunkedEncoding: false,
    shouldKeepAlive: true,
    _defaultKeepAlive: true,
    useChunkedEncodingByDefault: true,
    sendDate: true,
    _removedConnection: false,
    _removedContLen: false,
    _removedTE: false,
    _contentLength: null,
    _hasBody: true,
    _trailer: '',
    finished: false,
    _headerSent: false,
    socket: <ref *1> Socket {
      connecting: false,
      _hadError: false,
      _parent: null,
      _host: null,
      _readableState: [ReadableState],
      _events: [Object: null prototype],
      _eventsCount: 8,
      _maxListeners: undefined,
      _writableState: [WritableState],
      allowHalfOpen: true,
      _sockname: null,
      _pendingData: null,
      _pendingEncoding: '',
      server: [Server],
      _server: [Server],
      parser: [HTTPParser],
      on: [Function: socketListenerWrap],
      addListener: [Function: socketListenerWrap],
      prependListener: [Function: socketListenerWrap],
      _paused: false,
      _httpMessage: [Circular *3],
      timeout: 0,
      [Symbol(async_id_symbol)]: 20,
      [Symbol(kHandle)]: [TCP],
      [Symbol(kSetNoDelay)]: false,
      [Symbol(lastWriteQueueSize)]: 0,
      [Symbol(timeout)]: Timeout {
        _idleTimeout: -1,
        _idlePrev: null,
        _idleNext: null,
        _idleStart: 2049,
        _onTimeout: null,
        _timerArgs: undefined,
        _repeat: null,
        _destroyed: true,
        [Symbol(refed)]: false,
        [Symbol(kHasPrimitive)]: false,
        [Symbol(asyncId)]: 28,
        [Symbol(triggerId)]: 24
      },
      [Symbol(kBuffer)]: null,
      [Symbol(kBufferCb)]: null,
      [Symbol(kBufferGen)]: null,
      [Symbol(kCapture)]: false,
      [Symbol(kBytesRead)]: 0,
      [Symbol(kBytesWritten)]: 0,
      [Symbol(RequestTimeout)]: undefined
    },
    _header: null,
    _keepAliveTimeout: 5000,
    _onPendingData: [Function: bound updateOutgoingData],
    _sent100: false,
    _expect_continue: false,
    req: [Circular *2],
    locals: [Object: null prototype] {},
    [Symbol(kCapture)]: false,
    [Symbol(kNeedDrain)]: false,
    [Symbol(corked)]: 0,
    [Symbol(kOutHeaders)]: [Object: null prototype] {
      'x-powered-by': [Array],
      'access-control-allow-origin': [Array],
      vary: [Array]
    }
  },
  body: {},
  route: Route { path: '/', stack: [ [Layer] ], methods: { post: true } },
  [Symbol(kCapture)]: false,
  [Symbol(RequestTimeout)]:

所以這是我的問題：如何在 NodeJS 中獲取 post 引數？

uj5u.com熱心網友回復：

在評論中，在客戶端，您需要content type明確指定。

例如：

'Content-Type': 'application/json'

然后在您的快遞應用中：

console.log(req.body)

在問題的評論中歸功于@isolated 和@john

轉載請註明出處，本文鏈接：https://www.uj5u.com/houduan/374097.html

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