Fix angular http upgrade ionic

Question

This is an old angular code, I'm getting error with the Http, Headers, RequestOptions.

can someone help me fix this and get same function. Thanks in advance.

i used "import { HttpClient, HttpHeaders, HttpRequest } from '@angular/common/http';"

but some function are still not working properly here "let options = new HttpRequest({ headers: headers });"

import { Injectable } from '@angular/core';
import { Http, Headers, RequestOptions } from '@angular/http';
import 'rxjs/add/operator/map';

@Injectable()
export class PostProvider {
server: string = "http://localhost/server_api/"; // default


constructor(public http : Http) {

}

postData(body, file){
    let type = "application/json; charset=UTF-8";
    let headers = new Headers({ 'Content-Type': type });
    let options = new RequestOptions({ headers: headers });

    return this.http.post(this.server + file, JSON.stringify(body), options)
    .map(res => res.json());
}
}

Answer 1

Below Should Work Note the below Changes

• changed import {Http} from '@angular/http' to import {HttpClient} from '@angular/common/http'
• Removed JSON.stringify as it is not neccessary here
• Removed The mapping map(res => res.json()) as by default angular returns an Object. I have added typecasting <any> to return an any type observable. You can change this

import { Injectable } from '@angular/core';
import { HttpClient, HttpHeaders } from '@angular/common/http';

@Injectable()
export class PostProvider {
server = "http://localhost/server_api/"; 

constructor(public http : HttpClient) { }

postData(body, file) {
  const headers = new HttpHeaders({
    'Content-Type':"application/json; charset=UTF-8"
  })

  return this.http.post<any>(this.server + file, body, {headers})
}