Using a DynaActionForm instead of a custom subclass of ActionForm is relatively straightforward. You need to make changes in two places:
In struts-config.xml: change your <form-bean> to be an org.apache.struts.action.DynaActionForm instead of some subclass of ActionForm
<form-bean name="loginForm"type="org.apache.struts.action.DynaActionForm" >
<form-property name="userName" type="java.lang.String"/>
<form-property name="password" type="java.lang.String" />
</form-bean>
In your Action subclass that uses your form bean:
import org.apache.struts.action.DynaActionForm
downcast the ActionForm parameter in execute() to a DynaActionForm
access the form fields with get(field) rather than getField()
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionMessage;
import org.apache.struts.action.ActionMessages;
import org.apache.struts.action.DynaActionForm;
public class DynaActionFormExample extends Action {
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
DynaActionForm loginForm = (DynaActionForm) form;
ActionMessages errors = new ActionMessages();
if (((String) loginForm.get("userName")).equals("")) {
errors.add("userName", new ActionMessage(
"error.userName.required"));
}
if (((String) loginForm.get("password")).equals("")) {
errors.add("password", new ActionMessage(
"error.password.required"));
}