title: How to Resolve: TypeError: Cannot convert undefined or null to object
body: <p>I am creating an angular2 project and I am using ng2-uploader as the plugin for file upload. I want to drag and drop on a div and at the same time I want an upload button inside the div. After selecting a file to upload I got the error as 
  <strong>TypeError: Cannot convert undefined or null to object</strong>.</p>
  
  <p><strong>Html code is:</strong> </p>
  
  <pre><code>&lt;div [hidden]="!onUpload" ngFileDrop [options]="options" (onUpload)="handleUpload($event)" [ngClass]="{'file-over': hasBaseDropZoneOver}" (onFileOver)="fileOverBase($event)"&gt;
       &lt;input type="file" ngFileSelect [options]="options" (onUpload)="handleUpload($event)"&gt;
       &lt;p&gt;&lt;span&gt;Response: {{ uploadFile | json }}&lt;/span&gt;&lt;/p&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p><strong>Component is:</strong></p>
  
  <pre><code>import { Component, OnInit, NgModule, NgZone } from '@angular/core';
  
  @Component({
    selector: 'app-fileselect',
    templateUrl: './fileselect.component.html',
    styleUrls: ['./fileselect.component.css']
  })
  
  export class FileSelectComponent implements OnInit {
    zone: NgZone;
    hasBaseDropZoneOver: boolean = false;
    basicProgress: number = 0;
    uploadFile: any;
  
  constructor() {
      this.zone = new NgZone({ enableLongStackTrace: false });//file upload    
    }
  
  options: Object = {
      url: 'http://localhost:4200/assets/documents'
    };
  
  handleUpload(data): void {
      if (data &amp;&amp; data.response) {
        data = JSON.parse(data.response);
        this.uploadFile = data;
        this.zone.run(() =&gt; {
          this.basicProgress = data.progress.percent;
        });
      }
    } 
  
  fileOverBase(e: any): void {
          this.hasBaseDropZoneOver = e;
        }
      }
  </code></pre>