# MultiLineComboBox

## Content

The `MultiLineComboBox` control extends the [ComboBox](/wijmo/docs/Topics/Input/ComboBox/ComboBox) control with a multi-line text area. Use it to select or enter values such as addresses, notes, formatted labels, or hierarchical item text.
![multiline_combobox_basic](https://cdn.mescius.io/document-site-files/images/3c7113e2-10b3-45ed-8f3b-9fb1e0af2b74/multiline_combobox_basic-20261013.03406b.gif)
The control retains the item source, selection, and auto-complete behavior of `ComboBox`. The following example creates an editable control and populates it with multi-line values:

```typescript
import * as input from '@mescius/wijmo.input';

const locations = [
    'MESCIUS\n1-2-3 Chiyoda\nTokyo',
    '1600 Pennsylvania Avenue NW\nWashington, DC'
];

new input.MultiLineComboBox('#theComboString', {
    isEditable: true,
    itemsSource: locations
});
```

Set `isEditable` to `true` to allow users to enter multi-line values directly. Line breaks are stored as `\n` in the `text` value and are preserved during input, selection, and auto-complete. Multi-line values are displayed across multiple lines in both the text area and the drop-down list.
Unlike ComboBox, MultiLineComboBox sets `trimText` to `false` by default, preserving leading and trailing whitespace in the text value. Set `trimText` to `true` if you want the control to remove this whitespace.

>type=note
> **Note:** `inputType` always returns `"textarea"`. Setting this property has no effect.

## Keyboard Behavior

`MultiLineComboBox` gives native text editing behavior priority when the drop-down is closed. When the drop-down is open, navigation follows the standard `ComboBox` behavior.

| Key | Drop-down closed | Drop-down open |
| --- | ---------------- | -------------- |
| `Alt+Enter` | Inserts a line break. | Inserts a line break. |
| `Up` / `Down` | Moves the text caret. | Changes the selected item. |
| `PageUp` / `PageDown` | Moves the text caret to the beginning or end of the visible paragraph. | Changes the selected item. |
| `Shift+Alt+Up` / `Shift+Alt+Down` | Changes the selected item. | Changes the selected item. |
| Mouse wheel | Scrolls the text area. | Uses standard `ComboBox` drop-down behavior. |
| `Alt+Wheel` | Changes the selected item. | Does not change the selected item independently of the open drop-down. |

`Alt+Up` and `Alt+Down` open or close the drop-down list. The remaining keyboard commands are the same as in `ComboBox`.