# @ohos.app.ability.StartOptions (StartOptions)

**StartOptions** is used as an input parameter of [startAbility()](js-apis-inner-application-uiAbilityContext.md#uiabilitycontextstartability-1) to specify the window mode of an ability.

> **NOTE**
>
> The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.
> The APIs of this module can be used only in the stage model.

## Modules to Import

```ts
import StartOptions from '@ohos.app.ability.StartOptions';
```

## Attributes


**System capability**: SystemCapability.Ability.AbilityRuntime.Core

| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| [windowMode](js-apis-application-abilityConstant.md#abilityconstantwindowmode) | number | No| Window mode.|
| displayId | number | No| Display ID. The default value is **0**, indicating the current display.|