# Data
`react-bootstrap-typeahead` accepts an array of either strings or objects. If you pass in objects, each one should have a string property to be used as the label for display. By default, the key is named `label`, but you can specify a different key via the `labelKey` prop. If you pass an array of strings, the `labelKey` prop will be ignored.

The component will throw an error if any options are something other than a string or object with a valid `labelKey`.

The following are valid data structures:

### `Array<String>`
```jsx
var options = [
  'John',
  'Miles',
  'Charles',
  'Herbie',
];
```

### `Array<Object>` (w/default `labelKey`)
```jsx
var options = [
  {id: 1, label: 'John'},
  {id: 2, label: 'Miles'},
  {id: 3, label: 'Charles'},
  {id: 4, label: 'Herbie'},
];
```

### `Array<Object>` (w/custom `labelKey`)
In this case, you would need to set `labelKey="name"` on the component.

```jsx
var options = [
  {id: 1, name: 'John'},
  {id: 2, name: 'Miles'},
  {id: 3, name: 'Charles'},
  {id: 4, name: 'Herbie'},
];
```

## Duplicate Data
You may have unexpected results if your data contains duplicate options. For this reason, it is highly recommended that you pass in objects with unique identifiers (eg: an id) if possible.

## Data Sources
The component simply handles rendering and selection of the data that is passed in. It is agnostic about the data source, which should be handled separately. The [`AsyncTypeahead`](API.md#asynctypeahead) component is provided to help in cases where data is being fetched asynchronously from an endpoint.

[Next: Filtering](Filtering.md)