How to upload file in Angular2

your http service file:

import { Injectable } from "@angular/core";
import { ActivatedRoute, Router } from '@angular/router';
import { Http, Headers, Response, Request, RequestMethod, URLSearchParams, RequestOptions } from "@angular/http";
import {Observable} from 'rxjs/Rx';
import { Constants } from './constants';
declare var $: any;

@Injectable()
export class HttpClient {
  requestUrl: string;
  responseData: any;
  handleError: any;

  constructor(private router: Router, 
  private http: Http, 
  private constants: Constants, 
  ) {
    this.http = http;
  }

  postWithFile (url: string, postData: any, files: File[]) {

    let headers = new Headers();
    let formData:FormData = new FormData();
    formData.append('files', files[0], files[0].name);
    // For multiple files
    // for (let i = 0; i < files.length; i++) {
    //     formData.append(`files[]`, files[i], files[i].name);
    // }

    if(postData !=="" && postData !== undefined && postData !==null){
      for (var property in postData) {
          if (postData.hasOwnProperty(property)) {
              formData.append(property, postData[property]);
          }
      }
    }
    var returnReponse = new Promise((resolve, reject) => {
      this.http.post(this.constants.root_dir + url, formData, {
        headers: headers
      }).subscribe(
          res => {
            this.responseData = res.json();
            resolve(this.responseData);
          },
          error => {
            this.router.navigate(['/login']);
            reject(error);
          }
      );
    });
    return returnReponse;
  }
}

call your function (Component file):

onChange(event) {
    let file = event.srcElement.files;
    let postData = {field1:"field1", field2:"field2"}; // Put your form data variable. This is only example.
    this._service.postWithFile(this.baseUrl + "add-update",postData,file).then(result => {
        console.log(result);
    });
}

your html code:

<input type="file" class="form-control" name="documents" (change)="onChange($event)" [(ngModel)]="stock.documents" #documents="ngModel">

Improved onChange() method :

file: File;
  onChange(event: EventTarget) {
        let eventObj: MSInputMethodContext = <MSInputMethodContext> event;
        let target: HTMLInputElement = <HTMLInputElement> eventObj.target;
        let files: FileList = target.files;
        this.file = files[0];
        console.log(this.file);
    }

Here is the Angular 2 version

We needed to implement drag drop file input feature in one of our Angular 2 app.

We selected ng-file-upload for this.

We tried to follow the help page. As suggested, implemented drag-upload-input.html & drag-upload-input.component.ts like the following:

drag-upload-input.html

<!-- we only need single file upload -->
<input type="file" ng2FileSelect [uploader]="uploader" />

drag-upload-input.component.ts

import { Component } from '@angular/core';
import { FileUploader } from 'ng2-file-upload';

// const URL = '/api/';
const URL = 'https://evening-anchorage-3159.herokuapp.com/api/';

@Component({
  moduleId: module.id,
  selector: 'drag-upload-input',
  templateUrl: './drag-upload-input.html'
})
export class DragUploadInput {
  public uploader: FileUploader = new FileUploader({ url: URL });
  public hasBaseDropZoneOver: boolean = false;
  public hasAnotherDropZoneOver: boolean = false;

  public fileOverBase(e: any): void {
    this.hasBaseDropZoneOver = e;
  }

  public fileOverAnother(e: any): void {
    this.hasAnotherDropZoneOver = e;
  }
}

The app.module.ts has got FileUploadModule like this:

// File upload modules
import { FileUploadModule } from 'ng2-file-upload';
import { DragUploadInput } from './file-upload/drag-upload-input.component';

//other imports

@NgModule({
  imports: [ ... other imports
FileUploadModule
],
  declarations: [  ... other declarations
DragUploadInput],
  bootstrap: [AppComponent]
})
export class AppModule { }

And the systemjs.config.js looks like this:

(function (global) {
  System.config({
    // map tells the System loader where to look for things
    map: {
      // other libraries
      'ng2-file-upload': 'node_modules/ng2-file-upload',
    },
    packages: {
      // other packages
      ng2-file-upload': {
        main: 'ng2-file-upload.js',
        defaultExtension: 'js'
      }
    }
  });
})(this);

source