angular - 类型 'catch' 上不存在属性 'PromiseLike'

Question

我是一个 ionic 初学者，正在学习一些教程，当我试图捕捉一个错误时，我遇到了一些 typescript 问题......

Property 'catch' does not exist on type 'PromiseLike'

一定是过时的代码之类的。

问题就在这里。它发生在我尝试使用 catch 的每个页面上。

.then(() => { resolve(true);})
.catch((err) => {reject(err);})

/////////////////更新//////////这是 package.json 文件。我正在尝试创建一个 Firebase 聊天应用。

{
  "name": "chat",
  "version": "0.0.1",
  "author": "Ionic Framework",
  "homepage": "http://ionicframework.com/",
  "private": true,
  "scripts": {
    "clean": "ionic-app-scripts clean",
    "build": "ionic-app-scripts build",
    "lint": "ionic-app-scripts lint",
    "ionic:build": "ionic-app-scripts build",
    "ionic:serve": "ionic-app-scripts serve"
  },
  "dependencies": {
    "@angular/common": "5.0.3",
    "@angular/compiler": "5.0.3",
    "@angular/compiler-cli": "5.0.3",
    "@angular/core": "5.0.3",
    "@angular/forms": "5.0.3",
    "@angular/http": "5.0.3",
    "@angular/platform-browser": "5.0.3",
    "@angular/platform-browser-dynamic": "5.0.3",
    "@ionic-native/core": "4.4.0",
    "@ionic-native/file": "^4.4.2",
    "@ionic-native/file-chooser": "^4.4.2",
    "@ionic-native/file-path": "^4.4.2",
    "@ionic-native/splash-screen": "4.4.0",
    "@ionic-native/status-bar": "4.4.0",
    "@ionic/storage": "2.1.3",
    "angularfire2": "^5.0.0-rc.4",
    "cordova-plugin-file": "^5.0.0",
    "cordova-plugin-filechooser": "^1.0.1",
    "cordova-plugin-filepath": "^1.1.0",
    "firebase": "^4.7.0",
    "ionic-angular": "3.9.2",
    "ionicons": "3.0.0",
    "rxjs": "5.5.2",
    "sw-toolbox": "3.6.0",
    "zone.js": "0.8.18"
  },
  "devDependencies": {
    "@ionic/app-scripts": "3.1.4",
    "typescript": "2.4.2"
  },
  "description": "An Ionic project",
  "cordova": {
    "plugins": {
      "cordova-plugin-file": {},
      "cordova-plugin-filechooser": {},
      "cordova-plugin-filepath": {}
    }
  }
}

Answer 1

这个问题可能是因为推送时的“then”返回了一个 ThenableReference，它反过来导致返回一个“PromiseLike”。相反，如果您选择在推送时使用“set”，它将返回 then。所以这个方法应该是这样的

let promise = new Promise((resolve, reject) => {
      this.firerequest.child(request.recipient).push().set(
        { sender: request.sender }
      ).then(() => {
        resolve({ success: true })
      }).catch((error) => {
        reject(error);
      })
    })

    return promise;

您摘自 Raja Yogan 的聊天记录，所以我只是粘贴了来自不同提供商的代码。希望能帮助到你。