Angular2 indexeddb如何从查询返回值

我想从数据库中获取所有用户，为此我要：

// Get all users in the database.
getAllUsers() { 
this.db.getAll('users').then((users) => {
  console.log(users); //this logs all the users in the console.
}, (error) => {
  console.log(error);
});
}

在我的组件中，我执行以下操作：

// input the result in the array.
const users: any = this.i.getAllUsers();

如果我尝试：

// Get all users in the database.
getAllUsers() { 
this.db.getAll('users').then((users) => {
  return users; //i don't get a return value...
}, (error) => {
  console.log(error);
});
}

我没有得到任何回报值

如果我这样做：

return this.db.getAll('users');

---

我得到了整个method对象…

也许我在想basic，但是如果你把它放在一个变量中，它能工作吗

// Get all users in the database.
getAllUsers() { 
this.db.getAll('users').then((users) => {
  var allUsers = users; // <-here
}, (error) => {
  console.log(error);
});

//获取数据库中的所有用户。
getAllUsers（）{
this.db.getAll（'users'）。然后（（users）=>{
var alluser=用户；//{
console.log（错误）；
});

试试这个

getAllUsers() { 
 return this.db.getAll('users').then((users) => {
    return users;
   }, (error) => {
        console.log(error);
   });
}

问题解决了

  constructor(private r: ComponentFactoryResolver,
          private rs: RestService,
          private d: DataService,
          private i: IndexedDBService
) {
this.c = r.resolveComponentFactory(ChooseAccountProfileComponent);
this.db = new AngularIndexedDB('usersDB', 1);

this.db.createStore(1, (evt) => {
  const objectStore = evt.currentTarget.result.createObjectStore('users', {keyPath: 'id', unique: true});

  objectStore.createIndex('remembered', 'remembered');

}).then(() => {
  this.getAllUsers();
}, (error) => {
  console.log(error);
});
}

// Get all users in the database.
getAllUsers() {
this.db.getAll('users').then((users) => {
  let oldcounter = 0;
  const kleurenArray = ['#1ccc49', '#e10d6d', '#11afe0', '#7dd317', '#d95f16', '#b0990d', '#7510cc'];

  for (let i = 0; i < users.length; i++) {
    // put the json in an object.
    const obj = users[i];
    // Make the component.
    const cmpRef = this.v.createComponent(this.c);
    // Fill the component with the correct values.
    cmpRef.instance.name = obj.username;
    cmpRef.instance.id = obj.id;
    do {
      var counter = Math.floor(Math.random() * 7);
    }
    while (oldcounter === counter);
    oldcounter = counter;
    cmpRef.instance.image = '../../../assets/images/Avatars/avatar-    bg-col' + counter + '.png';
    cmpRef.instance.color = kleurenArray[counter];
  }
}, (error) => {
  console.log(error);
});
}

构造函数（私有r:ComponentFactoryResolver，
私人rs:RestService，
私人d：数据服务，
private i:IndexedBService
) {
this.c=r.resolveComponentFactory（选择AccountProfileComponent）；
this.db=新的AngularIndexedDB（'usersDB'，1）；
this.db.createStore（1，（evt）=>{
const objectStore=evt.currentTarget.result.createObjectStore（'users'，{keyPath:'id'，unique:true}）；
createIndex（'membered'，'membered'）；
}).然后（（）=>{
这个.getAllUsers（）；
}，（错误）=>{
console.log（错误）；
});
}
//获取数据库中的所有用户。
getAllUsers（）{
this.db.getAll（'users'）。然后（（users）=>{
设oldcounter=0；
常数kleurenArray=['#1ccc49'、'#e10d6d'、'#11afe0'、'#7dd317'、'#d95f16'、'#b090d'、'#7510cc']；
for（设i=0；i{
console.log（错误）；
});
}

---

我必须将所有方法放在同一个组件中，然后才能使用该变量。无论如何，谢谢！

感谢您的回答，但我得到了以下对象：[Log]ZoneAwarePromise（main.bundle.js，第493行）\uuuuuuu zone\u symbol\uu状态：true\uuuuuu zone\u symbol\uu值：未定义的ZoneAwarePromise原型捕获（onRejected）构造函数：function（）（OnImplemented，onRejected）对象原型（Uuuuuu defineGetter，Uuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuuu你必须解决它。它正在返回一个承诺，所以在解决它之后，你将能够得到结果。