# Accessing Properties of Untyped JavaScript Values
To read and write arbitrary properties from any untyped JavaScript value
regardless if it is an `instanceof` some JavaScript class or not, use [the
`js_sys::Reflect` APIs][js-sys-reflect]. These APIs are bindings to the
[JavaScript builtin `Reflect` object][mdn-reflect] and its methods.
You might also benefit from [using duck-typed
interfaces](./working-with-duck-typed-interfaces.html) instead of working with
untyped values.
## Reading Properties with `js_sys::Reflect::get`
[API documentation for `js_sys::Reflect::get`.](https://rustwasm.github.io/wasm-bindgen/api/js_sys/struct.Reflect.html#method.get)
A function that returns the value of a property.
#### Rust Usage
```rust
let value = js_sys::Reflect::get(&target, &property_key)?;
```
#### JavaScript Equivalent
```js
let value = target[property_key];
```
## Writing Properties with `js_sys::Reflect::set`
[API documentation for `js_sys::Reflect::set`.](https://rustwasm.github.io/wasm-bindgen/api/js_sys/struct.Reflect.html#method.set)
A function that assigns a value to a property. Returns a boolean that is true if
the update was successful.
#### Rust Usage
```rust
js_sys::Reflect::set(&target, &property_key, &value)?;
```
#### JavaScript Equivalent
```js
target[property_key] = value;
```
## Determining if a Property Exists with `js_sys::Reflect::has`
[API documentation for `js_sys::Reflect::has`.](https://rustwasm.github.io/wasm-bindgen/api/js_sys/struct.Reflect.html#method.has)
The JavaScript `in` operator as function. Returns a boolean indicating whether
an own or inherited property exists on the target.
#### Rust Usage
```rust
if js_sys::Reflect::has(&target, &property_key)? {
// ...
} else {
// ...
}
```
#### JavaScript Equivalent
```js
if (property_key in target) {
// ...
} else {
// ...
}
```
## But wait — there's more!
See [the `js_sys::Reflect` API documentation][js-sys-reflect] for the full
listing of JavaScript value reflection and introspection capabilities.
[js-sys-reflect]: https://rustwasm.github.io/wasm-bindgen/api/js_sys/struct.Reflect.html
[mdn-reflect]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Reflect