[Home](./index.md) > [rc-js-util](./rc-js-util.md) > [stringNormalizeEmptyToUndefined](./rc-js-util.stringnormalizeemptytoundefined.md) ## stringNormalizeEmptyToUndefined() function Replaces length 0 strings with `undefined`. **Signature:** ```typescript export declare function stringNormalizeEmptyToUndefined(input: string | null | undefined): string | undefined; ``` ## Parameters

Parameter	Type	Description
input	string \| null \| undefined

**Returns:** string \| undefined `input` if it's a `string` of length greater than 0, otherwise `undefined`. ## Remarks See [stringNormalizeEmptyToUndefined()](./rc-js-util.stringnormalizeemptytoundefined.md).