从服务订阅数据时，类型为 void 时不存在错误属性订阅？

Question

我在 angular 7 应用程序上工作，我遇到错误属性订阅在类型上不存在

从服务订阅数据时作废。

应用程序组件上的订阅数据功能上显示错误 那么如果可能的话，如何解决这个问题呢？

allReportCategories:any[];
ngOnInit() {

this._displayreport.getallReportCategories().subscribe((data: any[]) => {  
this.allReportCategories = data;  
}); 
}

显示报表服务 TS

allReportCategories:any[];

getallReportCategories(){
return 
this.allReportCategories=[
{
"reportCategoryID": 1,
"reportCategory": "Dashboard Parametric",
"isDeleted": false,
"menuIcon": "icon-home"
},
{
"reportCategoryID": 2,
"reportCategory": "Monitor Reports",
"isDeleted": false,
"menuIcon": "icon-list"
},
{
"reportCategoryID": 3,
"reportCategory": "Other Reports",
"isDeleted": false,
"menuIcon": "icon-docs"
},
{
"reportCategoryID": 4,
"reportCategory": "PCN Flow",
"isDeleted": false,
"menuIcon": "icon-list"
},
{
"reportCategoryID": 5,
"reportCategory": "Compliance By Document",
"isDeleted": false,
"menuIcon": "icon-home"
}
];
}

示例存在于堆栈BLIZ上，如下所示：

https://stackblitz.com/edit/create-1arrvm?file=app%2Fdisplayreport.service.ts

更具体地回答我的问题

我在这里改变什么：

this._displayreport.getallReportCategories().subscribe

Answer 1

您需要创建可观察订阅

例：-

显示报表服务 TS

import { BehaviorSubject } from 'rxjs';

getallReportCategories(){
const allReportCategories = [
{
"reportCategoryID": 1,
"reportCategory": "Dashboard Parametric",
"isDeleted": false,
"menuIcon": "icon-home"
},
{
"reportCategoryID": 2,
"reportCategory": "Monitor Reports",
"isDeleted": false,
"menuIcon": "icon-list"
},
{
"reportCategoryID": 3,
"reportCategory": "Other Reports",
"isDeleted": false,
"menuIcon": "icon-docs"
},
{
"reportCategoryID": 4,
"reportCategory": "PCN Flow",
"isDeleted": false,
"menuIcon": "icon-list"
},
{
"reportCategoryID": 5,
"reportCategory": "Compliance By Document",
"isDeleted": false,
"menuIcon": "icon-home"
}
];

return new BehaviorSubject(allReportCategories)
}

在组件中

allReportCategories:any[];
ngOnInit() {

this._displayreport.getallReportCategories().subscribe((data: any[]) => {  
this.allReportCategories = data;  
}); 
}