Shapefile-js on Angular 8

Shapefile-jsonAngular8.js

/*
Hi all,

For those of you, using the amazing package shapefile-js written by calvinmetcalf: https://github.com/calvinmetcalf/shapefile-js/
Here is a brief decription, on how to make it work on Angular 8:

First install the package with:

npm install shpjs --save

Import it on your component:
*/
import * as shp from 'shpjs';

//Then from your component, create an async function, which will call a function on a service, to read the file uploaded (A ZIP containing the shp and all related files):

async SHPtoGEOJSON(form: any) {
    await this.Service.readFileContent(file)
      .toPromise().then(
        res => {
          shp(res).then(function (geojson) {
            console.log(geojson);
          })
        }
      );
  }

//Last but not least, on the Service:

  readFileContent(file: File) {
    let fileReader: FileReader = new FileReader();
    fileReader.readAsArrayBuffer(file);
    return Observable.create(observer => {
      fileReader.onloadend = () => {
        observer.next(fileReader.result);
        observer.complete();
      };
    });
  }

/*
Oh! And on polyfills.ts you need to add :
*/
(window as any).global = window;
declare var global: (any);
declare var require: (any);
global.Buffer = global.Buffer || require('buffer').Buffer;

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