HTMLCollection extension type

The HTMLCollection interface represents a generic collection (array-like object similar to arguments) of elements (in document order) and offers methods and properties for selecting from the list.

An HTMLCollection in the HTML DOM is live; it is automatically updated when the underlying document is changed. For this reason it is a good idea to make a copy (e.g., using Array.from) to iterate over if adding, moving, or removing nodes.

This interface is called HTMLCollection for historical reasons, because before the modern DOM, collections implementing this interface could only have HTML elements as their items.

This interface was an attempt to create an unmodifiable list and only continues to be supported to not break code that's already using it. Modern APIs represent list structures using types based on JavaScript arrays, thus making many array methods available, and at the same time imposing additional semantics on their usage (such as making their items read-only).

These historical reasons do not mean that you as a developer should avoid HTMLCollection. You don't create HTMLCollection objects yourself, but you get them from APIs such as Document.getElementsByClassName, and these APIs are not deprecated. However, be careful of the semantic differences from a real array.

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API documentation sourced from MDN Web Docs.

on

• JSObject

Implemented types

• JSObject

Available extensions

• JSAnyOperatorExtension
• JSAnyUtilityExtension
• JSObjectUnsafeUtilExtension
• NullableUndefineableJSAnyExtension

Properties

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

length → int

The HTMLCollection.length property returns the number of items in a HTMLCollection.

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

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 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.

item(int index) → Element?

The HTMLCollection method item() returns the element located at the specified offset into the collection.

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.

namedItem(String name) → Element?

The namedItem() method of the HTMLCollection interface returns the first Element in the collection whose id or name attribute match the specified name, or null if no element matches.

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.

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 and returns 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.