Achieve invisible upload

import { Component } from '@angular/core';
import { createElement } from '@syncfusion/ej2-base';
import { SelectedEventArgs } from '@syncfusion/ej2-angular-inputs';

/**
 * Default Uploader Default Component
 */
@Component({
    selector: 'app-root',
    templateUrl: 'default.html',
    styleUrls: ['index.css']
})
export class AppComponent {

    public path: Object = {
        saveUrl: 'https://aspnetmvc.syncfusion.com/services/api/uploadbox/Save',
        removeUrl: 'https://aspnetmvc.syncfusion.com/services/api/uploadbox/Remove'
    };
  public allowExtensions: string = '.png, .jpg, .jpeg';
  public onSelected(args: SelectedEventArgs):void {
    for(let i = 0; i< args.filesData.length ; i++){
        let liparentDiv = createElement('div',  { className: 'image-list'});
        let liImage = createElement('img',  { className: 'image'});
        liparentDiv.appendChild(liImage);
        this.readURL(liImage, args.filesData[i]);
        document.getElementById('preview').appendChild(liparentDiv);
    }
    args.cancel=true;
}

public readURL(liImage: HTMLElement, file: any):void {
    let imgPreview: HTMLImageElement = liImage as HTMLImageElement;
    let imageFile: File = file.rawFile;
    let reader: FileReader = new FileReader();
    reader.addEventListener( 'load', () => {
        imgPreview.src = reader.result;
    }, false);
    if (imageFile) {
        reader.readAsDataURL(imageFile);
    }
};
}

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { UploaderModule } from '@syncfusion/ej2-angular-inputs';

/**
 * Module
 */
@NgModule({
    imports: [
        BrowserModule, UploaderModule
    ],
    declarations: [AppComponent],
    bootstrap: [AppComponent]
})
export class AppModule {
}

import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
import { enableProdMode } from '@angular/core';
import { AppModule } from './app.module';

enableProdMode();
platformBrowserDynamic().bootstrapModule(AppModule);

#container {
  visibility: hidden;
}

#loader {
color: #008cff;
height: 40px;
left: 45%;
position: absolute;
top: 45%;
width: 30%;
}

.control_wrapper {
  max-width: 500px;
  min-width: 245px;
  margin: auto;
}

#preview {
border: 2px dashed #ddd;
padding: 15px;
}

.image-list {
width: 134px;
height: 117px;
margin-right: 4px;
border: 1px solid lightgrey;
display: inline-block;
}

.image {
width: 134px;
height: 117px;
margin-right: 4px;
display: inline-block;
}

.e-control {
border : 0;
}

.e-control ul {
border: 1px solid #ddd;
}

.e-control .e-file-select,
.e-control .e-file-drop {
display: none;
}