Some types of places allow recipients to enter data during the ceremony, such as text input places. The content entered in these places is rendered on the documents once the recipients complete their participation. In some cases, you may also want to access this input data via the API. You can use Captures to store values entered by recipients during the ceremony.

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Defining Captures

Places that allow arbitrary recipient input—like text input places—have a capture_as property. This property lets you define a key to identify the captured value within the envelope.
capture_as keys must be unique within the envelope.
For example, the following Text Input Place asks a recipient to enter an 8-digit reference number during the signing ceremony: 
// POST /v1/envelopes
{
    "documents": [
        {
            //...
            "places": [
                {
                    "key": "order_reference_number",
                    "type": "text_input",
                    "hint": "Your 8-digit reference code",
                    "prompt": "12345678",
                    "format": "/^[0-9]{8}$/",
                    "recipient_key": "customer",
                    "capture_as": "reference"
                }
                //...
            ]
        }
        //...
    ]
}
When the customer (the Recipient) completes the ceremony, her reference number will be captured using the key reference in the envelope’s captures object: 
{
    // other envelope properties
    //...
    "captures": {
        "reference": "11223344"
    }
    //...
}