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1. Default values entered when the form was created in the Form Designer
2. Values from an XML document(s) sent in the Post request for the form or OnInit.
3. URL parameters appended to the form URL via the  _data URL parameter
4. Values retrieved as the form loads from any Document URIs
5. And finally default values set via Business Rules as the form loads and during use. See Setting default values in rules and using REST Services in Rules for further details.

_data

Form fields can be initialized directly from the form's HTTP URL. You can do this by using the special (reserverd) URL parameter called _data. Below is an example of a form initialized via _data. The syntax for _data is based on Rison. This form was initialized by appending the following to the URL from the form's Share Email/Web Page link URL.

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