Flex中mx:Image组件动态调用Tomcat工程以外图片的方法

<mx:Image source="@Embed('C:/test.PNG')" />

但是很快发现，Embed标签是在编译期就把图片加载进swf文件中的，无法实现动态更换图片的功能。

解决的办法是:

新建一个Servlet来实现图片读取。

ImageShowServlet.java

public class ImageShowServlet extends HttpServlet {

 private static final long serialVersionUID = -3481832826439542244L;

 @Override
 protected void doGet(HttpServletRequest req, HttpServletResponse resp)
   throws ServletException, IOException {
  
  processRequest(req, resp);
 }

 @Override
 protected void doPost(HttpServletRequest req, HttpServletResponse resp)
   throws ServletException, IOException {
  
  processRequest(req, resp);
 }

 protected void processRequest(HttpServletRequest request,
   HttpServletResponse response) throws ServletException, IOException {
  
  String imgName = request.getParameter("imagename");
  ResourceBundle resourceBundel = ResourceBundle.getBundle("application");
  String imgPath = resourceBundel.getString("img_root");
  
       File imgFile = new File(imgPath + imgName);
       if(imgFile.exists()) {
        
        response.reset();
           response.setContentType("application/octet-stream");
           response.setCharacterEncoding("utf-8");
           response.setHeader("Content-disposition", "filename=" + imgName);
           
        InputStream is = new FileInputStream(imgFile);
           OutputStream outputStream = response.getOutputStream();
           int data = -1; 
           while((data = is.read()) != -1) {
            outputStream.write(data); 
           }
           outputStream.flush();
           outputStream.close();
       }
 }
}

Flex通过访问这个Servlet来实现图片加载：

var imgName : String = "test.PNG";
var imgUrl : String = "./imageshow?imagename=" + imgName;
imgroot.source = imgUrl; //imgroot.load(imgUrl);也可以