# ui:emptyValueInput **Reference:** [View Source](https://github.com/jramke/fluid-primitives/tree/main/Classes/ViewHelpers/EmptyValueInputViewHelper.php) Renders the input a form control submits while it is empty. A browser leaves an unchecked checkbox or a field without a value out of the form, so Extbase never learns that the property was cleared. This input submits `''` under the name of the control, and the control disables it while it has a value. ```html ``` Place it in the template of a component whose context uses `HasEmptyValueInputTrait`, before the native input that holds the value: PHP keeps the last value under a name, so the real value wins. It renders nothing while the context has no `emptyValueName`. A name that ends with `[]` is submitted without the brackets (`tags`, not `tags[]`), which Extbase maps to an empty array or ObjectStorage, where `['']` would hold one empty entry. `data-empty-value` carries the full name, for the client to read an empty list. Call `syncEmptyValueInput()` from the `render()` of the component to disable the input while the control has a value. ## Arguments _None_