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API > @angular/platform-browser

By

Predicates for use with DebugElement's query functions.

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

Static methods

all()

Match all elements.
static all(): Predicate<DebugElement>
      
      static all(): Predicate<DebugElement>

Parameters

There are no parameters.

Returns

Predicate<DebugElement>

Example

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

css()

Match elements by the given CSS selector.
static css(selector: string): Predicate<DebugElement>
      
      static css(selector: string): Predicate<DebugElement>

Parameters

selector

Type: string.

Returns

Predicate<DebugElement>

Example

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

directive()

Match elements that have the given directive present.
static directive(type: Type<any>): Predicate<DebugElement>
      
      static directive(type: Type<any>): Predicate<DebugElement>

Parameters

type

Type: Type.

Returns

Predicate<DebugElement>

Example

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