PerformanceEntry extension type

The PerformanceEntry object encapsulates a single performance metric that is part of the browser's performance timeline.

The Performance API offers built-in metrics which are specialized subclasses of PerformanceEntry. This includes entries for resource loading, event timing, (FID), and more.

A performance entry can also be created by calling the Performance.mark or Performance.measure methods at an explicit point in an application. This allows you to add your own metrics to the performance timeline.

The PerformanceEntry instances will always be one of the following subclasses:

• LargestContentfulPaint
• LayoutShift
• PerformanceEventTiming
• PerformanceLongAnimationFrameTiming
• PerformanceLongTaskTiming
• PerformanceMark
• PerformanceMeasure
• PerformanceNavigationTiming
• PerformancePaintTiming
• PerformanceResourceTiming
• PerformanceScriptTiming
• PerformanceServerTiming
• TaskAttributionTiming
• VisibilityStateEntry

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API documentation sourced from MDN Web Docs.

on

• JSObject

Implemented types

• JSObject

Implementers

• LargestContentfulPaint
• PerformanceEventTiming
• PerformanceMark
• PerformanceMeasure
• PerformancePaintTiming
• PerformanceResourceTiming

Available extensions

• JSAnyOperatorExtension
• JSAnyUtilityExtension
• JSObjectUnsafeUtilExtension
• NullableUndefineableJSAnyExtension

Properties

duration → double

The read-only duration property returns a that is the duration of the . The meaning of this property depends on the value of this entry's PerformanceEntry.entryType.

no setter

entryType → String

The read-only entryType property returns a string representing the type of performance metric that this entry represents.

no setter

hashCode → int

The hash code for this object.

no setter, inherited

isDefinedAndNotNull → bool

Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension

no setter

isNull → bool

Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension

Whether this value corresponds to JavaScript null.

no setter

isTruthy → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of !!this in JavaScript.

no setter

isUndefined → bool

Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension

Whether this value corresponds to JavaScript undefined.

no setter

isUndefinedOrNull → bool

Available on JSAny?, provided by the NullableUndefineableJSAnyExtension extension

no setter

name → String

The read-only name property of the PerformanceEntry interface is a string representing the name for a performance entry. It acts as an identifier, but it does not have to be unique. The value depends on the subclass.

no setter

not → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of !this in JavaScript.

no setter

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

startTime → double

The read-only startTime property returns the first recorded for this . The meaning of this property depends on the value of this entry's PerformanceEntry.entryType.

no setter

Methods

add(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this + any in JavaScript.

and(JSAny? any) → JSAny?

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this && any in JavaScript.

callMethod<R extends JSAny?>(JSAny method, [JSAny? arg1, JSAny? arg2, JSAny? arg3, JSAny? arg4]) → R

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Calls method on this JSObject with up to four arguments.

callMethodVarArgs<R extends JSAny?>(JSAny method, [List<JSAny?>? arguments]) → R

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Calls method on this JSObject with a variable number of arguments.

dartify() → Object?

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Converts a JavaScript JSON-like value to the Dart equivalent if possible.

delete(JSAny property) → JSBoolean

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Deletes the property with key property from this JSObject.

divide(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this / any in JavaScript.

equals(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this == any in JavaScript.

exponentiate(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this ** any in JavaScript.

getProperty<R extends JSAny?>(JSAny property) → R

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

The value of the property key property of this JSObject.

greaterThan(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this > any in JavaScript.

greaterThanOrEqualTo(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this >= any in JavaScript.

has(String property) → bool

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Shorthand helper for hasProperty to check whether this JSObject contains the property key property, but takes and returns a Dart value.

hasProperty(JSAny property) → JSBoolean

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Whether or not this JSObject contains the property key property.

instanceof(JSFunction constructor) → bool

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Whether this JSAny? is an instanceof constructor.

instanceOfString(String constructorName) → bool

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Whether this JSAny? is an instanceof the constructor that is defined by constructorName, which is looked up in the globalContext.

isA<T extends JSAny?>() → bool

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Whether this JSAny? is an instance of the JavaScript type that is declared by T.

lessThan(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this < any in JavaScript.

lessThanOrEqualTo(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this <= any in JavaScript.

modulo(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this % any in JavaScript.

multiply(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this * any in JavaScript.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

notEquals(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this != any in JavaScript.

or(JSAny? any) → JSAny?

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this || any in JavaScript.

setProperty(JSAny property, JSAny? value) → void

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Write the value of property key property of this JSObject.

strictEquals(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this === any in JavaScript.

strictNotEquals(JSAny? any) → JSBoolean

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this !== any in JavaScript.

subtract(JSAny? any) → JSAny

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this - any in JavaScript.

toJSON() → JSObject

The toJSON() method is a ; it returns a JSON representation of the PerformanceEntry object.

toString() → String

A string representation of this object.

inherited

typeofEquals(String typeString) → bool

Available on JSAny?, provided by the JSAnyUtilityExtension extension

Whether the result of typeof on this JSAny? is typeString.

unsignedRightShift(JSAny? any) → JSNumber

Available on JSAny?, provided by the JSAnyOperatorExtension extension

The result of this >>> any in JavaScript.

Operators

operator ==(Object other) → bool

The equality operator.

inherited

operator [](String property) → JSAny?

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Shorthand helper for getProperty to get the value of the property key property of this JSObject, but takes a Dart value.

operator []=(String property, JSAny? value) → void

Available on JSObject, provided by the JSObjectUnsafeUtilExtension extension

Shorthand helper for setProperty to write the value of the property key property of this JSObject, but takes a Dart value.