'Observable <object>'类型中不存在属性'concatMap'？

Question

我从Angular 4升级到5，并将Http替换为HttpClient。我从http.post调用中移除了链接地图，该调用现在返回Observable<Object>，但在我的组件中，它现在正在抱怨concatMap does not exist on type Observable<Object>。以下是我正在做的一个例子：

//service
import { HttpClient} from '@angular/common/http';

constructor(private _http: HttpClient) { }

registerDomain()
{

return this._http.post('/api/domain/domain/register', {});
}

//component
registerDomain(caseId,domain) {
    return this._domainService.registerDomain(caseId,domain)
      .concatMap(operation => this.getOperationDetail(operation.OperationId,this.caseId,domain))
      .concatMap(() => this.createRecordSets(domain));
  }

我可以在Observable<Object>上看到地图和mergeMap，但不能看到concatMap

Answer 1

尝试导入：

import 'rxjs/add/operator/concatMap'

Answer 2

您需要使用管道

registerDomain(caseId,domain) {
    return this._domainService.registerDomain(caseId,domain)
      .pipe(
         concatMap(operation => this.getOperationDetail(operation.OperationId,this.caseId,domain))
         concatMap(() => this.createRecordSets(domain))
    );
  }