In Svelte, stores are reactive objects that hold a value and notify subscribers whenever the value changes. Svelte provides three main types of built-in stores: writable, readable, and derived. These help in managing state effectively across components.
A writable store is the most common type of store. It allows both reading and updating the value. You can use the set and update methods to modify its state.
A readable store is read-only for the components that subscribe to it. The logic for updating its value is encapsulated inside the store itself, making it ideal for data like timers or system states.
A derived store creates a new store whose value is based on one or more other stores. It automatically recalculates whenever the dependencies change.
You can use the $store syntax in Svelte components to automatically subscribe to store values.
Writable stores can be read and updated using
setandupdate.Readable stores can only be read externally, with updates managed internally.
Derived stores compute their value based on other stores and update automatically.
Use the
$storesyntax in components for automatic subscription and cleanup.