Combine [NgStyle] With Condition (if..else)

Question

I have read NgStyle Documentation For Angular2. Little bit confusing for me. Any idea on how to use NgStyle with condition like (if...else) to set background image of any element?

Answer 1

You can use this as follows:

<div [style.background-image] = "value ? 'url('+imgLink+')' : 'url('+defaultLink+')'"></div>

Answer 2

The above answers did not work for me so, i decided to improve this.

You should work with url(''), and not with value.

<li *ngFor="let item of items">
  <div 
    class="img-wrapper" 
    [ngStyle]="{'background-image': !item.featured ? 'url(\'images/img1.png\')' : 'url(\'images/img2.png\')'}">
  </div>
</li>

Answer 3

One can also use this kind of condition:

<div [ngStyle]="myBooleanVar && {'color': 'red'}"></div>

It requires a bit less string concatenation...

Answer 4

Using a ternary operator inside the ngStyle binding will function as an if/else condition.

<div [ngStyle]="{'background-image': 'url(' + value ? image : otherImage + ')'}"></div>