How do I send data from Struts action to javascript?_问答_开发者

How do I send data from Struts action to javascript?

开发者 https://www.devze.com 2023-02-24 19:43 出处：网络

I\'m trying to create a webb application using Struts 2 and javascript and I\'m having some trouble passing data from my action into my javascript.

I'm trying to create a webb application using Struts 2 and javascript and I'm having some trouble passing data from my action into my javascript.

This is the list I'm trying to send/access:

List<MarkerClass> markers;

MarkerClass is defined acoprding to belove:

final class MarkerClass  
{  
    public Integer objectId;  
    public String street;  
    public String streetNumber;  
    public String zip;  
    public String city;  
    public Integer statusId;  
    public Float lattitude;  
    public Float longitude;  
}

The action also includes a getter for开发者_如何学C markers:

public List<MarkerClass> getMarkers()
{
    return markers;
}

In my jsp-file I have tried doing this:

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE html>
<html>
<head>

<script type="text/javascript">

function initialize() 
{
    var titel = "";
    for(var i, "${markers}")
    {
        titel = titel+ "${markers[i].street}";
    }
}

The browser substitutes "${markers}" with "[se.fubar.test.MarkerClass@37a4, se.fubar.test.MarkerClass@9ad97c]"

I'm guessing there is a better and smarter way to do this but since I'm a bit new to Struts and is trying to code while under the influence of a migrane the answer elludes me.

You cannot just use a struts variable in a javascript function and expect it to work. Remember that the ${...} stuff gets processed before the HTML for the page is sent to the browser. By the time the javascript is rendered at the browser, you are only left with the textual representations. What you will need to do is something like (check the syntax, I haven't used this stuff i a while):

function initialize() {
    var title = "";
    <c:foreach var="marker" list="${markers}">
         title = title + "${marker.street}";
    </c:foreach>
}

Something along those lines anyway... Basically the Javascript seen by your browser will look like

function initialize() {
    var title = "";
    title = title + "Street1";
    title = title + "Street2";
    title = title + "Street3";
    title = title + "Street4";
}

I hope that makes sense and is related to what you were asking. By the way, there are usually better ways of accomplishing this functionality that building dynamic js etc. Probably there are built in Struts 2 components that you can use?

you would have to set that variable in request or in session and then access it using a <c:out jsp tag like so

var myVar= '<c:out value="${requestScope.myVar}"/>';

then use the var inside your js.

In case you set an object in request or session you have to use the get method to access the value of an attribute then use it like so:

var myVar= '<c:out value="${requestScope.myObj.attribute}"/>';

(assuming you getter method is getAttribute)

it is not possible to access data in session or request directly from js hope this helps

You could convert the object to json on the server (see http://www.json.org/java/index.html ) and then call eval() on the string to get a javascript representation of your object.

you can try accessing it something like this. but you have to use a loop to fetch each object from the list place it on the value stack and than fetch each object of it.else you can ask ognl to do it for you.something like

<script type="text/javascript">

function initialize() 
{
    var titel = "";
    for(var i, "${markers}")
    {
        titel = titel+ <s:property value="%{markers.get(i).street}">;
    }
}

just try it since OGNL has capacity to access the object on the value stack