Struct web_sys :: ObserverCallback Copy item path

impl ObserverCallback

pub fn get_handle_event(&self) -> Option<Function>

Get the handleEvent field of this object.

This API requires the following crate features to be activated: ObserverCallback

impl ObserverCallback

pub fn set_handle_event(&self, val: &Function)

Change the handleEvent field of this object.

This API requires the following crate features to be activated: ObserverCallback

impl ObserverCallback

pub fn new() -> Self

Construct a new ObserverCallback.

This API requires the following crate features to be activated: ObserverCallback

pub fn handle_event(&mut self, val: &Function) -> &mut Self

👎Deprecated: Use set_handle_event() instead.

Methods from Deref<Target = Object>§

pub fn constructor(&self) -> Function

The constructor property returns a reference to the Object constructor function that created the instance object.

pub fn has_own_property(&self, property: &JsValue) -> bool

The hasOwnProperty() method returns a boolean indicating whether the object has the specified property as its own property (as opposed to inheriting it).

pub fn is_prototype_of(&self, value: &JsValue) -> bool

The isPrototypeOf() method checks if an object exists in another object’s prototype chain.

pub fn property_is_enumerable(&self, property: &JsValue) -> bool

The propertyIsEnumerable() method returns a Boolean indicating whether the specified property is enumerable.

pub fn to_locale_string(&self) -> JsString

The toLocaleString() method returns a string representing the object. This method is meant to be overridden by derived objects for locale-specific purposes.

pub fn to_string(&self) -> JsString

The toString() method returns a string representing the object.

pub fn value_of(&self) -> Object

The valueOf() method returns the primitive value of the specified object.

Methods from Deref<Target = JsValue>§

pub fn as_f64(&self) -> Option<f64>

Returns the f64 value of this JS value if it’s an instance of a number.

If this JS value is not an instance of a number then this returns None.

pub fn is_string(&self) -> bool

Tests whether this JS value is a JS string.

pub fn as_string(&self) -> Option<String>

If this JS value is a string value, this function copies the JS string value into wasm linear memory, encoded as UTF-8, and returns it as a Rust String.

To avoid the copying and re-encoding, consider the JsString::try_from() function from js-sys instead.

If this JS value is not an instance of a string or if it’s not valid utf-8 then this returns None.

§UTF-16 vs UTF-8

JavaScript strings in general are encoded as UTF-16, but Rust strings are encoded as UTF-8. This can cause the Rust string to look a bit different than the JS string sometimes. For more details see the documentation about the str type which contains a few caveats about the encodings.

pub fn as_bool(&self) -> Option<bool>

Returns the bool value of this JS value if it’s an instance of a boolean.

If this JS value is not an instance of a boolean then this returns None.

pub fn is_null(&self) -> bool

Tests whether this JS value is null

pub fn is_undefined(&self) -> bool

Tests whether this JS value is undefined

pub fn is_symbol(&self) -> bool

Tests whether the type of this JS value is symbol

pub fn is_object(&self) -> bool

Tests whether typeof self == "object" && self !== null.

pub fn is_array(&self) -> bool

Tests whether this JS value is an instance of Array.

pub fn is_function(&self) -> bool

Tests whether the type of this JS value is function.

pub fn is_bigint(&self) -> bool

Tests whether the type of this JS value is bigint.

pub fn js_typeof(&self) -> JsValue

Applies the unary typeof JS operator on a JsValue.

pub fn js_in(&self, obj: &JsValue) -> bool

Applies the binary in JS operator on the two JsValues.

pub fn is_truthy(&self) -> bool

Tests whether the value is “truthy”.

pub fn is_falsy(&self) -> bool

Tests whether the value is “falsy”.

pub fn loose_eq(&self, other: &JsValue) -> bool

Compare two JsValues for equality, using the == operator in JS.

pub fn bit_not(&self) -> JsValue

Applies the unary ~ JS operator on a JsValue.

pub fn unsigned_shr(&self, rhs: &JsValue) -> u32

Applies the binary >>> JS operator on the two JsValues.

pub fn checked_div(&self, rhs: &JsValue) -> JsValue

Applies the binary / JS operator on two JsValues, catching and returning any RangeError thrown.

pub fn pow(&self, rhs: &JsValue) -> JsValue

Applies the binary ** JS operator on the two JsValues.

pub fn lt(&self, other: &JsValue) -> bool

Applies the binary < JS operator on the two JsValues.

pub fn le(&self, other: &JsValue) -> bool

Applies the binary <= JS operator on the two JsValues.

pub fn ge(&self, other: &JsValue) -> bool

Applies the binary >= JS operator on the two JsValues.

pub fn gt(&self, other: &JsValue) -> bool

Applies the binary > JS operator on the two JsValues.

pub fn unchecked_into_f64(&self) -> f64

Applies the unary + JS operator on a JsValue. Can throw.

Trait Implementations§

impl AsRef<JsValue> for ObserverCallback

fn as_ref(&self) -> &JsValue

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<Object> for ObserverCallback

fn as_ref(&self) -> &Object

Converts this type into a shared reference of the (usually inferred) input type.

impl AsRef<ObserverCallback> for ObserverCallback

fn as_ref(&self) -> &ObserverCallback

Converts this type into a shared reference of the (usually inferred) input type.

impl Clone for ObserverCallback

fn clone(&self) -> ObserverCallback

Returns a copy of the value. Read more

1.0.0 · source§

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more

impl Debug for ObserverCallback

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more

impl Default for ObserverCallback

fn default() -> Self

Returns the “default value” for a type. Read more

impl Deref for ObserverCallback

type Target = Object

The resulting type after dereferencing.

fn deref(&self) -> &Object

Dereferences the value.

impl From<JsValue> for ObserverCallback

fn from(obj: JsValue) -> ObserverCallback

Converts to this type from the input type.

impl From<ObserverCallback> for JsValue

fn from(obj: ObserverCallback) -> JsValue

Converts to this type from the input type.

impl From<ObserverCallback> for Object

fn from(obj: ObserverCallback) -> Object

Converts to this type from the input type.

impl FromWasmAbi for ObserverCallback

type Abi = <JsValue as FromWasmAbi>::Abi

The wasm ABI type that this converts from when coming back out from the ABI boundary.

unsafe fn from_abi(js: Self::Abi) -> Self

Recover a Self from Self::Abi. Read more

impl<'a> IntoWasmAbi for &'a ObserverCallback

type Abi = <&'a JsValue as IntoWasmAbi>::Abi

The wasm ABI type that this converts into when crossing the ABI boundary.

fn into_abi(self) -> Self::Abi

Convert self into Self::Abi so that it can be sent across the wasm ABI boundary.

impl IntoWasmAbi for ObserverCallback

type Abi = <JsValue as IntoWasmAbi>::Abi

The wasm ABI type that this converts into when crossing the ABI boundary.

fn into_abi(self) -> Self::Abi

Convert self into Self::Abi so that it can be sent across the wasm ABI boundary.

impl JsCast for ObserverCallback

fn instanceof(val: &JsValue) -> bool

Performs a dynamic instanceof check to see whether the JsValue provided is an instance of this type. Read more

fn unchecked_from_js(val: JsValue) -> Self

Performs a zero-cost unchecked conversion from a JsValue into an instance of Self Read more

fn unchecked_from_js_ref(val: &JsValue) -> &Self

Performs a zero-cost unchecked conversion from a &JsValue into an instance of &Self. Read more

fn has_type<T>(&self) -> bool
where T: JsCast,

Test whether this JS value has a type T. Read more

fn dyn_into<T>(self) -> Result<T, Self>
where T: JsCast,

Performs a dynamic cast (checked at runtime) of this value into the target type T. Read more

fn dyn_ref<T>(&self) -> Option<&T>
where T: JsCast,

Performs a dynamic cast (checked at runtime) of this value into the target type T. Read more

fn unchecked_into<T>(self) -> T
where T: JsCast,

Performs a zero-cost unchecked cast into the specified type. Read more

fn unchecked_ref<T>(&self) -> &T
where T: JsCast,

Performs a zero-cost unchecked cast into a reference to the specified type. Read more

fn is_instance_of<T>(&self) -> bool
where T: JsCast,

Test whether this JS value is an instance of the type T. Read more

fn is_type_of(val: &JsValue) -> bool

Performs a dynamic check to see whether the JsValue provided is a value of this type. Read more

impl LongRefFromWasmAbi for ObserverCallback

type Abi = <JsValue as LongRefFromWasmAbi>::Abi

Same as RefFromWasmAbi::Abi

type Anchor = ObserverCallback

Same as RefFromWasmAbi::Anchor

unsafe fn long_ref_from_abi(js: Self::Abi) -> Self::Anchor

Same as RefFromWasmAbi::ref_from_abi

impl OptionFromWasmAbi for ObserverCallback

fn is_none(abi: &Self::Abi) -> bool

Tests whether the argument is a “none” instance. If so it will be deserialized as None, and otherwise it will be passed to FromWasmAbi.

impl<'a> OptionIntoWasmAbi for &'a ObserverCallback

fn none() -> Self::Abi

Returns an ABI instance indicating “none”, which JS will interpret as the None branch of this option. Read more

impl OptionIntoWasmAbi for ObserverCallback

fn none() -> Self::Abi

Returns an ABI instance indicating “none”, which JS will interpret as the None branch of this option. Read more

impl PartialEq for ObserverCallback

fn eq(&self, other: &ObserverCallback) -> bool

Tests for self and other values to be equal, and is used by ==.

1.0.0 · source§

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl RefFromWasmAbi for ObserverCallback

type Abi = <JsValue as RefFromWasmAbi>::Abi

The wasm ABI type references to Self are recovered from.

type Anchor = ManuallyDrop<ObserverCallback>

The type that holds the reference to Self for the duration of the invocation of the function that has an &Self parameter. This is required to ensure that the lifetimes don’t persist beyond one function call, and so that they remain anonymous.