useContext

Reads the current value of a context.

• For createContext<T>() (default-less): returns the value from the nearest enclosing Provider, or throws ContextNotFoundError if none is mounted. Return type is T (no narrowing required).
• For createContext<T>(defaultValue): returns the value from the nearest enclosing Provider, or defaultValue if none is mounted.

In Solid, useContext is the canonical way to read context. There is no need for a wrapper hook that throws on missing Provider — the default-less form already does that, and its return type is T.

Import

import { useContext } from "solid-js";

Type signature

function useContext<T>(context: Context<T>): T;

Parameters

context

A context returned from createContext

Return value

The value provided by the nearest enclosing Provider, or the default if one was supplied to createContext

Examples

const TodosContext = createContext<TodosCtx>();

function TodoList() {
  const [todos, { addTodo }] = useContext(TodosContext); // throws if no Provider
  // ...
}

Related types

ContextNotFoundError

class ContextNotFoundError extends Error {
  constructor() {
    super(
      __DEV__
        ? "Context must either be created with a default value or a value must be provided before accessing it."
        : ""
    );
  }
}