# react/no-unused-class-component-methods

> Disallow methods and properties of a class component that the class never uses

A handler that's no longer wired to any element stays in the class and looks like it still matters. This rule reports a method or a property of a class component, or of a `createReactClass` component, that's never read through `this` in the same component.

Lifecycle methods such as `render` and `componentDidMount`, `state`, and static members are never reported.

## Configure

Off by default. To turn it on:

```toml bunfig.toml
[lint.rules]
"react/no-unused-class-component-methods" = "error" # or "warn"
```

## Examples

Reported:

```jsx
class SearchBox extends React.Component {
  timeout = 300;

  handleChange(event) {
    this.props.onSearch(event.target.value);
  }

  render() {
    return <input />;
  }
}
```

Not reported:

```jsx
class SearchBox extends React.Component {
  timeout = 300;

  handleChange = event => {
    setTimeout(() => this.props.onSearch(event.target.value), this.timeout);
  };

  render() {
    return <input onChange={this.handleChange} />;
  }
}
```

## When not to use it

The rule only looks inside the component. If a parent calls a method through a ref, such as `searchBox.current.focus()`, the method is reported even though it's used.