I have the below directive:
@Directive({
selector: '[changeColor]',
exportAs:'changeColor'
})
export class ColorDirective {
constructor(elem: ElementRef, renderer: Renderer2) {
renderer.setStyle(elem.nativeElement, 'color', 'red');
}
}
I have the below template:
<h1 changeColor>Hello</h1>
This works as expected and displays "Hello" in red. But, when I try to access a reference of the directive I get an error. For example, the below code:
<h1 #x=changeColor>Hello</h1>
{{x}}
produces the below error "There is no directive with "exportAs" set to "changeColor""
. Where am I going wrong?
You didn't apply the changeColor
directive in the second snippet, since there is no changeColor
attribute on the h1
. It should be
<h1 changeColor #x="changeColor">Hello</h1>
can you explain why the selector of an attribute should be within [ ]
Because that's the syntax for CSS selectors (the same you're using in a CSS stylesheet):
[foo]
selects any element with an attribute named foo .foo
selects any element with a CSS class named foo foo
selects any element named foo bar[foo]:not(.baz)
selects any element named bar, which has an attribute named foo and doesn't have a class named baz.
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