Struct js_sys::Object [−][src]
#[repr(transparent)]pub struct Object { /* fields omitted */ }
Expand description
Implementations
The constructor property returns a reference to the Object
constructor
function that created the instance object.
The Object.create()
method creates a new object, using an existing
object to provide the newly created object’s prototype.
The static method Object.defineProperty()
defines a new
property directly on an object, or modifies an existing
property on an object, and returns the object.
The Object.defineProperties()
method defines new or modifies
existing properties directly on an object, returning the
object.
The Object.entries()
method returns an array of a given
object’s own enumerable property [key, value] pairs, in the
same order as that provided by a for…in loop (the difference
being that a for-in loop enumerates properties in the
prototype chain as well).
The Object.freeze()
method freezes an object: that is, prevents new
properties from being added to it; prevents existing properties from
being removed; and prevents existing properties, or their enumerability,
configurability, or writability, from being changed, it also prevents
the prototype from being changed. The method returns the passed object.
The Object.fromEntries()
method transforms a list of key-value pairs
into an object.
The Object.getOwnPropertyDescriptor()
method returns a
property descriptor for an own property (that is, one directly
present on an object and not in the object’s prototype chain)
of a given object.
The Object.getOwnPropertyDescriptors()
method returns all own
property descriptors of a given object.
The Object.getOwnPropertyNames()
method returns an array of
all properties (including non-enumerable properties except for
those which use Symbol) found directly upon a given object.
The Object.getOwnPropertySymbols()
method returns an array of
all symbol properties found directly upon a given object.
The Object.getPrototypeOf()
method returns the prototype
(i.e. the value of the internal [[Prototype]] property) of the
specified object.
The hasOwnProperty()
method returns a boolean indicating whether the
object has the specified property as its own property (as opposed to
inheriting it).
The Object.isExtensible()
method determines if an object is extensible
(whether it can have new properties added to it).
The Object.isFrozen()
determines if an object is frozen.
The Object.isSealed()
method determines if an object is sealed.
The isPrototypeOf()
method checks if an object exists in another
object’s prototype chain.
The Object.keys()
method returns an array of a given object’s property
names, in the same order as we get with a normal loop.
The Object
constructor creates an object wrapper.
The Object.preventExtensions()
method prevents new properties from
ever being added to an object (i.e. prevents future extensions to the
object).
The propertyIsEnumerable()
method returns a Boolean indicating
whether the specified property is enumerable.
The Object.seal()
method seals an object, preventing new properties
from being added to it and marking all existing properties as
non-configurable. Values of present properties can still be changed as
long as they are writable.
The Object.setPrototypeOf()
method sets the prototype (i.e., the
internal [[Prototype]]
property) of a specified object to another
object or null
.
The toLocaleString()
method returns a string representing the object.
This method is meant to be overridden by derived objects for
locale-specific purposes.
The toString()
method returns a string representing the object.
The valueOf()
method returns the primitive value of the
specified object.
The Object.values()
method returns an array of a given object’s own
enumerable property values, in the same order as that provided by a
for...in
loop (the difference being that a for-in loop enumerates
properties in the prototype chain as well).
Methods from Deref<Target = JsValue>
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
.
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.
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
.
Tests whether this JS value is undefined
Tests whether the type of this JS value is function
.
Trait Implementations
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs the conversion.
Performs a dynamic instanceof
check to see whether the JsValue
provided is an instance of this type. Read more
Performs a zero-cost unchecked conversion from a JsValue
into an
instance of Self
Read more
Performs a zero-cost unchecked conversion from a &JsValue
into an
instance of &Self
. Read more
Test whether this JS value has a type T
. Read more
Performs a dynamic cast (checked at runtime) of this value into the
target type T
. Read more
Performs a dynamic cast (checked at runtime) of this value into the
target type T
. Read more
Performs a zero-cost unchecked cast into the specified type. Read more
Performs a zero-cost unchecked cast into a reference to the specified type. Read more
Test whether this JS value is an instance of the type T
. Read more
Performs a dynamic check to see whether the JsValue
provided
is a value of this type. Read more
type Abi = <JsValue as RefFromWasmAbi>::Abi
type Abi = <JsValue as RefFromWasmAbi>::Abi
The wasm ABI type references to Self
are recovered from.
type Anchor = ManuallyDrop<Object>
type Anchor = ManuallyDrop<Object>
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. Read more
Recover a Self::Anchor
from Self::Abi
. Read more
Auto Trait Implementations
impl RefUnwindSafe for Object
impl UnwindSafe for Object
Blanket Implementations
Mutably borrows from an owned value. Read more
type Abi = <T as IntoWasmAbi>::Abi
type Abi = <T as IntoWasmAbi>::Abi
Same as IntoWasmAbi::Abi
Same as IntoWasmAbi::into_abi
, except that it may throw and never
return in the case of Err
. Read more