[javascript] How to set Angular 4 background image?

This works for me:

put this in your markup:

<div class="panel panel-default" [ngStyle]="{'background-image': getUrl()}">

then in component:

getUrl()
{
  return "url('http://estringsoftware.com/wp-content/uploads/2017/07/estring-header-lowsat.jpg')";
}