@angular/common

NgClass

directive

Adds and removes CSS classes on an HTML element.

  
    class NgClass {}

Adds and removes CSS classes on an HTML element.

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.

              <some-element [ngClass]="'first second'">...</some-element>    <some-element [ngClass]="['first', 'second']">...</some-element>    <some-element [ngClass]="{'first': true, 'second': true, 'third': false}">...</some-element>    <some-element [ngClass]="stringExp|arrayExp|objExp">...</some-element>    <some-element [ngClass]="{'class1 class2 class3' : true}">...</some-element>

klass

string

ngClass

string | string[] | Set<string> | { [klass: string]: any; }