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angular / 12 / api / platform-browser / by.html

By

class final

Predicates for use with DebugElement's query functions.

class By {
  static all(): Predicate<DebugNode>
  static css(selector: string): Predicate<DebugElement>
  static directive(type: Type<any>): Predicate<DebugNode>
}

Static methods

all()

Match all nodes.

static all(): Predicate<DebugNode>

Parameters

There are no parameters.

Returns

Predicate<DebugNode>

Usage Notes

Example
debugElement.query(By.all());
css()

Match elements by the given CSS selector.

static css(selector: string): Predicate<DebugElement>

Parameters
selector string
Returns

Predicate<DebugElement>

Usage Notes

Example
debugElement.query(By.css('[attribute]'));
directive()

Match nodes that have the given directive present.

static directive(type: Type<any>): Predicate<DebugNode>

Parameters
type Type
Returns

Predicate<DebugNode>

Usage Notes

Example
debugElement.query(By.directive(MyDirective));

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Licensed under the Creative Commons Attribution License 4.0.
https://v12.angular.io/api/platform-browser/By