How to “logic:iterate” just one object?

问题

So, I have this code:

logic:iterate name="nameForm" property="name" id="nameId" indexId="index"
bean:write name="nameId" property="field1"/
bean:write name="nameId" property="field2"/

This works great because I'm receiving a "table of objects" so I can do the iterate without issues.

Now, on another page I need to do the same but the issue is I am not receiving a "table of objects" but an object itself. I tried it nonetheless and - as expected - got the error: Cannot create iterator for this collection

I've RTFM'd and I'm still more confused than before.
I get how the "name" inside the "logic:iterate" points to the form name in the struts-config, now I need to do the same with just one bean, any help please?

回答1:

You can use a bean name with the <logic:iterate>, but it should be a collection or array, or implement Iterable. Here's the example of the tag usage.

In Struts, you can use logic:iterate tag to iterate over collections. Here’re the example:

Iterate over a list/array (Object)

Create a normal list with few "user" objects and store it into HttpServletRequest as name "listUsers".

public class User{

  String username;
  String url;

    //getter and setter methods
}


...

public class PrintMsgAction extends Action{

  public ActionForward execute(ActionMapping mapping,ActionForm form,
      HttpServletRequest request,HttpServletResponse response) 
        throws Exception {

      List<User> listUsers = new ArrayList<User>();

      listUsers.add(new User("user1", "http://www.user1.com"));
      listUsers.add(new User("user2", "http://www.user2.com"));
      listUsers.add(new User("user3", "http://www.user3.com"));
      listUsers.add(new User("user4", "http://www.user4.com"));

      request.setAttribute("listUsers", listUsers);

      return mapping.findForward("success");
  }

}

Inside the logic tag, you can use the "name" attribute (listUsers) to get the list value, while "property" attribute to display the object property value.

<%@taglib uri="http://struts.apache.org/tags-bean" prefix="bean"%>
<%@taglib uri="http://struts.apache.org/tags-logic" prefix="logic"%>
<html>
<head>
</head>
<body>
<h1>Struts <logic:iterate> example</h1>

<logic:iterate name="listUsers" id="listUserId">
<p>
  List Users <bean:write name="listUserId" property="username"/> , 
  <bean:write name="listUserId" property="url"/>
</p>
</logic:iterate>

</body>
</html>

来源：https://stackoverflow.com/questions/34788885/how-to-logiciterate-just-one-object

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collections

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