Radio button fields are handled in EWD as follows. Let's imagine we have an HTML form in our EWD page with the following radio button field:
Male: <input type="radio" name="sex" value="m" /><br> Female: <input type="radio" name="sex" value="f" />
To pre-check a value when the page is displayed, in the page's pre-page script, set the corresponding EWD Session variable to the value you want checked, mapping via the field's name, eg
In this case the Male radio button will be checked when the page is displayed. Of course, typically you'll determine the value to pre-check based on information retrieved from the database.
When the form is submitted, the associated Action Script simply gets the value from the matching EWD Session variable, eg:
Click the Enterprise Web Developer/Examples tab for worked examples.