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Can ngClass use ternary operator in Angular 2?

In Angular 1, the code below works well.

<div ng-class="$varA === $varB ? 'css-class-1' : 'css-class-2'">

But when I try to do similar thing in Angular 2. It does not work.

I already added directives: [NgClass]

<div [ngClass]="varA === varB ? 'css-class-1' : 'css-class-2'">

How should I write in Angular 2, thanks!

EDIT: It was my mistake, I accidentally added { } to the whole varA === varB ? 'css-class-1' : 'css-class-2'. So ngClass still can use ternary operator in Angular 2.

Solution

  • Yes. What you wrote works:

    <div [ngClass]="varA === varB ? 'css-class-1' : 'css-class-2'">

    Plunker

    The result of the expression on the the right-hand side has to evaluate to one of the following:

    • a string of space-delimited CSS class names (this is what your expression returns)
    • an Array of CSS class names
    • an Object, with CSS class names as keys, and booleans as values

    Maybe you had some other error in your code?