Utility methods to manipulatepackage:js annotated JavaScript interopobjects in cases where the name to call is not known at runtime.

You should only use these methods when the same effect cannot be achievedwith@JS() annotations.

Properties

globalThis→Object

no setter

objectPrototype→Object?

Returns theObject prototype. Equivalent toObject.prototype.

no setter

Functions

add<T>(Object?first,Object?second)→ T

Perform JavaScript addition (+) on two values.

allowInterop<F extendsFunction>(Ff)→ F

Returns a wrapper around functionf that can be called from JavaScriptusingpackage:js JavaScript interop.

allowInteropCaptureThis(Functionf)→Function

Returns a wrapper around functionf that can be called from JavaScriptusingpackage:js JavaScript interop, passing JavaScriptthis as thefirst argument.

and<T>(Object?first,Object?second)→ T

Perform JavaScript logical and comparison (&&) of two expressions.

callConstructor<T>(Objectconstr,List<Object?>?arguments)→ T

callMethod<T>(Objecto,Objectmethod,List<Object?>args)→ T

createDartExport<T extendsObject>(TdartObject)→Object

Given a Dart object that is marked exportable, creates a JS object literalthat forwards to that Dart class. Look at the@JSExport annotation todetermine what constitutes "exportable" for a Dart class. The object literalwill be a map of export names (which are either the written instance membernames or their rename) to their respective Dart instance members.

createStaticInteropMock<T extendsObject,U extendsObject>(UdartMock, [Object?proto =null])→ T

Given a@staticInterop type T and an instancedartMock of a Dart classU that implements the external extension members of T, creates a forwardingmock.

dartify(Object?o)→Object?

Effectively the inverse ofjsify,dartify Takes a JavaScript object, andconverts it to a Dart based object. Only JS primitives, arrays, or 'map'like JS objects are supported.

delete<T>(Objecto,Objectproperty)→bool

Perform JavaScript delete operator (delete) on the given property of thegiven object.

divide<T>(Object?first,Object?second)→ T

Perform JavaScript division (/) on two values.

equal<T>(Object?first,Object?second)→bool

Perform JavaScript equality comparison (==) on two values.

exponentiate<T>(Object?first,Object?second)→ T

Perform JavaScript exponentiation (**) on two values.

getProperty<T>(Objecto,Objectname)→ T

greaterThan<T>(Object?first,Object?second)→bool

Perform JavaScript greater than comparison (>) of two values.

greaterThanOrEqual<T>(Object?first,Object?second)→bool

Perform JavaScript greater than or equal comparison (>=) of two values.

hasProperty(Objecto,Objectname)→bool

instanceof(Object?o,Objecttype)→bool

Check whethero is an instance oftype.

instanceOfString(Object?element,StringobjectType)→bool

Likeinstanceof only takes aString for the object name instead of aconstructor object.

isJavaScriptArray(dynamicvalue)→bool

Returnstrue if a given object is a JavaScript array.

isJavaScriptSimpleObject(dynamicvalue)→bool

Returnstrue if a given object is a simple JavaScript object.

isTruthy<T>(Object?o)→bool

Determines if the given object is truthy or falsy.

jsify(Object?object)→ dynamic

Recursively converts a JSON-like collection to JavaScript compatiblerepresentation.

lessThan<T>(Object?first,Object?second)→bool

Perform JavaScript less than comparison (<) of two values.

lessThanOrEqual<T>(Object?first,Object?second)→bool

Perform JavaScript less than or equal comparison (<=) of two values.

modulo<T>(Object?first,Object?second)→ T

Perform JavaScript remainder (%) on two values.

multiply<T>(Object?first,Object?second)→ T

Perform JavaScript multiplication (*) on two values.

newObject<T>()→ T

not<T>(Object?o)→ T

Perform JavaScript logical not (!) on the given object.

notEqual<T>(Object?first,Object?second)→bool

Perform JavaScript inequality comparison (!=) on two values.

objectGetPrototypeOf(Object?object)→Object?

Returns the prototype of a given object. Equivalent toObject.getPrototypeOf.

objectKeys(Object?object)→List<Object?>

Returns the keys for a given object. Equivalent toObject.keys(object).

or<T>(Object?first,Object?second)→ T

Perform JavaScript logical or comparison (||) of two expressions.

promiseToFuture<T>(ObjectjsPromise)→Future<T>

Converts a JavaScript Promise to a DartFuture.

setProperty<T>(Objecto,Objectname,T?value)→ T

strictEqual<T>(Object?first,Object?second)→bool

Perform JavaScript strict equality comparison (===) on two values.

strictNotEqual<T>(Object?first,Object?second)→bool

Perform JavaScript strict inequality comparison (!==) on two values.

subtract<T>(Object?first,Object?second)→ T

Perform JavaScript subtraction (-) on two values.

typeofEquals<T>(Object?o,Stringtype)→bool

Perform JavaScripttypeof operator on the given object and determine ifthe result is equal to the given type. Exposes the wholetypeof equalexpression to maximize browser optimization.

unsignedRightShift(Object?leftOperand,Object?rightOperand)→num

Perform JavaScript unsigned right shift operator (>>>) on the given leftoperand by the amount specified by the given right operand.

Exceptions / Errors

NullRejectionException

Exception for when aJSPromise that is converted viaJSPromiseToFuture.toDart is rejected with anull orundefined value.