# useEventState

This hook save last emitted event data in state and return state.

{% hint style="info" %}
If You want use hooks, hocs or component decorator You must use EventrixProvider in Your application. Go to "EventrixProvider" page in "Context" section for more details.
{% endhint %}

{% tabs %}
{% tab title="Javascript" %}

```jsx
import React from 'react';
import { useEventState, useEmit } from 'eventrix';

const UndoDeleteUserButton = () => {
    const [eventState, setEventState] = useEventState('removeUser');
    const emit = useEmit();
    const addUser = useCallback(() => {
        emit('addUser', eventState);
        setEventState(null);
    }, [emit, eventState, setEventState]);
    if (!eventState) {
        return null;
    }
    return (
        <button onClick={addUser}>
            Undo user delete
        </button>
    );
}
```

{% endtab %}

{% tab title="Typescript" %}

```typescript
import React from 'react';
import { useEventState, useEmit } from 'eventrix';
import { User } from './interfaces';

const UndoDeleteUserButton = () => {
    const [eventState, setEventState] = useEventState<User | undefined | null>('removeUser');
    const emit = useEmit<User>();
    const addUser = useCallback(() => {
        if (eventState) {
            emit('addUser', eventState);
            setEventState(null);
        }
    }, [emit, eventState, setEventState]);
    if (!eventState) {
        return null;
    }
    return (
        <button onClick={addUser}>
            Undo user delete
        </button>
    );
}
```

{% endtab %}
{% endtabs %}


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