Question

我开始研究异步管道，并且对此深感困惑。

func getAllApi(completion:@escaping DataCallback){
    guard isInternetAvailabele() else {
        completion(nil)
        return
    }
    // AppSyncManager.Client() is AWSAppSyncClient Object
    AppSyncManager.Client().fetch(query: GetlAllPostQuery(input: allInputs), cachePolicy:.fetchIgnoringCacheData) {
        (result, error) in
        var haveError:Bool = error != nil
        if let _ = result?.data?.getAllPostings?.responseCode {haveError = false} else {haveError = true}
        if haveError  {
            print(error?.localizedDescription ?? "")
            completion(nil)
            return
        }

        if result != nil{
            completion(result)
        }else{
            completion(nil)
        }
    }
}

这是我的组件。

Task <06E9BBF4-5731-471B-9B7D-19E5E504E57F>.<45> HTTP load failed (error code: -1001 [1:60])
Task <D91CA952-DBB5-4DBD-9A90-98E2069DBE2D>.<46> HTTP load failed (error code: -1001 [1:60])
Task <06E9BBF4-5731-471B-9B7D-19E5E504E57F>.<45> finished with error - code: -1001
Task <D91CA952-DBB5-4DBD-9A90-98E2069DBE2D>.<46> finished with error - code: -1001

这是我的component.html

我遇到错误import { Component, OnDestroy } from '@angular/core'; import { AngularFireDatabase } from 'angularfire2/database'; @Component({ selector: 'app-root', templateUrl: './app.component.html', styleUrls: ['./app.component.css'] }) export class AppComponent { courses$; constructor(db: AngularFireDatabase) { this.courses$ = db.list('/courses'); } } 我是Angular的初学者，所以请帮忙。

Answer 1

将代码更改为：

this.courses$ = db.list('/courses').valueChanges();

这将解决您的问题。

管道“ AsyncPipe”的InvalidPipeArgument

1 个答案: