[Home](./index.md) > [rc-js-util](./rc-js-util.md) > [Range2d](./rc-js-util.range2d.md) > [unionRange](./rc-js-util.range2d.unionrange.md) ## Range2d.unionRange() method **Signature:** ```typescript unionRange(_range: IReadonlyRange2d, _writeTo?: Range2d): Range2d; ``` ## Parameters

Parameter	Type	Description
\_range	[IReadonlyRange2d](./rc-js-util.ireadonlyrange2d.md)<[TTypedArray](./rc-js-util.ttypedarray.md)>
\_writeTo	[Range2d](./rc-js-util.range2d.md)<TResult>	_(Optional)_

**Returns:** [Range2d](./rc-js-util.range2d.md)<TResult>