How to pass parameters across JSP iframe implementation code_javascript skills

The form is separated from the operation page
When the button is pressed, the click or onclick event is triggered
Pass a unique parameter to the sub-page JSP,
In the sub-page, it is responsible for query and judgment logic,
JSP:FORWARD Tried it and reported an error directly

Copy the code The code is as follows:

Sub page

Copy code The code is as follows:

<%
String tf_application= (request.getParameter("t_application"));
%>
<%=tf_application%>
<%
if(tf_application !=null)
{
tf_application = null;
}
%>
<%=tf_application%>

Try to use request or session, how to use onclick attribute on getAtturibute is a question problem