Question

我试图对我使用http.get从服务返回的可观察对象进行排序。订阅后，我曾尝试对服务中的数据以及组件中的数据进行排序。但是我总是得到错误排序不是一个函数。我是Angular的新手，但我一直坚持这样做。感谢您的帮助。谢谢

JSON sample

"data": [

    {
        "codeValue": 2,
        "codeType": 145,
        "description": "ASSIMILATION"
    },
    {
        "codeValue": 3,
        "codeType": 145,
        "description": "BANKRUPTCY"
    },
    {
        "codeValue": 4,
        "codeType": 145,
        "description": "BID TENDER"
    },

event.interface.ts

export interface IEventInterface {
codeValue: number;
codeType: number;
description: string;

}


Service.ts
getEventType():
{

    return this.http.get<IEventInterface[]>('/gpscaservices/v1/system- 
 descriptions?codeType=145&codeValue=');

}

Create.Component.ts

orderedEvent: any;
eventTypes: any;

this._dataService.getEventType().subscribe({
next: (response: IEventInterface[]) => {
            this.eventTypes = response  ;
            this.sortBy('description');
        }

sortBy(field: string ) {
               this.eventTypes.sort((a: any, b: any) =>{
        if (a[field] < b[field]) {
            return -1;
        } else if (a[field] > b[field]) {
            return 1;
        } else {
            return 0;
        }
    });

        this.orderedEvent = this.eventTypes;

Create.Component.html

nx-option *ngFor="let eventType of orderedEvent.data" 
[value]="eventType.codeValue">
{{ eventType.description }}
/nx-option>

Answer 1

我认为您错过了data字段。

sortBy(field: string ){
  this.eventTypes.data.sort((a: any, b: any) => {
    if (a[field] < b[field]) {
      return -1;
    } else if (a[field] > b[field]) {
      return 1;
    } else {
      return 0;
    }
  });

  this.orderedEvent = this.eventTypes;
}

最好定义一个明确的类型，而不要使用任何类型。

export interface EventData {
  data: IEventInterface[]
}

orderedEvent: EventData;
eventTypes: EventData;

Answer 2

您可以像这样设置排序功能

sortEventTypes(sortString : string){
   this.eventTypes.sort(function (a, b) {
     return a[sortString] - b[sortString];
  });
}

尝试对Observable进行排序时，Angular 8错误排序不是函数

2 个答案: