# Lookup Field API

| **Lookup field**                                                                                                                                                     |
| -------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| *\<lookup name=”string” placeholder=”string” optional=”boolean” allowCustomValue=”boolean” search=”boolean” documentId=”Id” relatedTo=”string” columnUuid=”UUID” />* |

#### Lookup Field attributes

* **name** — string, length from 1 up to 128 symbols, restricted symbols &, “, <, >, field name used to fill in on envelope, unique for document, mandatory attribute.
* **placeholder** — field placeholder displayable on template and envelope, length from 0 up to 1024 symbols, if empty on envelope will be displayed field name, optional attribute.
* **optional** — boolean, defines if field to be filled in optionally or not on envelope, if not set default value false, optional attribute.
* **allowCustomValue** — boolean, defines if custom value would be acceptable on envelope, optional attribute.
* **search** — boolean, defines if field is searchable on envelope search or not, if not set default value false, optional attribute.
* **documentId** — id, document id where dictionary field which will be looked up is located, mandatory attribute.
* **relatedTo** — string, name of dictionary to which lookup will be connected, mandatory attribute.
* **columnUuid** — UUID of dictionary column, which value should be taken as text value, mandatory attribute.


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