Angular: conditional class with *ngClass

Question

What is wrong with my Angular code? I am getting:

Cannot read property \'remove\' of undefined at BrowserDomAdapter.removeClass ...

Answer 1

In Angular 7.X

The CSS classes are updated as follows, depending on the type of the expression evaluation:

• string - the CSS classes listed in the string (space delimited) are added

• Array - the CSS classes declared as Array elements are added

• Object - keys are CSS classes that get added when the expression given in the value evaluates to a truthy value, otherwise they are removed.

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