我定义了一个接口
export interface IEmployee
{
maNV?:number,
hoTen?:string,
gioiTinh?:string,
ngaySinh?:Date,
diaChi?:string,
cmnd?:string,
sdt?:string,
luong?:number,
ngayBatDauLam?:Date,
maNguoiQuanLy?:number,
isDelete?:boolean
}
我创建了一个employee.json包含一些员工信息的文件：
[
{"maNV":1,"hoTen":"nguyen quang du","gioiTinh":"nam","ngaySinh":"03/02/1999","diaChi":"Hà Tây","cmnd":"1131131231231232","sdt":3123123141,"luong":300,"ngayBatDauLam":"03/01/2020","maNguoiQuanLy":1,"isDelete":false},
{"maNV":2,"hoTen":"nguyen thi duyen","gioiTinh":"nu","ngaySinh":"03/02/1999","diaChi":"Hà Tây","cmnd":"1131131231231232","sdt":3123123141,"luong":300,"ngayBatDauLam":"03/01/2020","maNguoiQuanLy":1,"isDelete":false},
{"maNV":3,"hoTen":"khuat quang chien","gioiTinh":"nam","ngaySinh":"03/02/1999","diaChi":"Hà Tây","cmnd":"1131131231231232","sdt":3123123141,"luong":300,"ngayBatDauLam":"03/01/2020","maNguoiQuanLy":1,"isDelete":false}
]
然后，我创建了一项服务以从中获取员工数据 employee.json
import { Injectable } from '@angular/core';
import {HttpClient} from '@angular/common/http'
import {IEmployee} from './employee/employee'
import {Observable} from 'rxjs'
@Injectable({
providedIn: 'root'
})
export class EmployeeService {
private _url:string="../assets/data/employees.json";
constructor(private http:HttpClient) {}
getEmployees():Observable<IEmployee[]>
{
return this.http.get<IEmployee[]>(this._url);
}
}
之后，我创建了一个组件来从method中获取员工数据getEmployee()，主要代码如下：
public data:Array<IEmployee>;
constructor(private service:EmployeeService){}
ngOnInit():void
{
this.service.getEmployees().subscribe(data=>this.data=data) ;
console.log(this.data);
}
我发现this.data是undefined。我不知道为什么在定义它的时候为什么Array<IEmployee>。并帮助我将其转换为typeArray<IEmployee>
那是因为您在记录数据之前被httpClient捕获，因此请记住，httpClient.get是一个异步方法，如果您希望将console.log移到订阅中，它应该可以正常工作：
ngOnInit():void
{
this.service.getEmployees().subscribe(data=>{
this.data=data;
console.log(this.data);
}) ;
}
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