Servlet+AJAX实现数据处理显示

实现功能：在输入框中输入字符，用AJAX传到后台Servlet处理后加上随机数，并返回到前台显示。
一、写前台jsp页面index.jsp

	  <%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>



  
    
    
	
  
  
   
   
   
  

二、写后台Servlet加random随机数，关键代码如下：

public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		request.setCharacterEncoding("utf-8"); //用utf-8转换获得传输过来的码
		response.setContentType("text/html");
		PrintWriter out = response.getWriter();
		String txt = request.getParameter("txt");
		
//		String tx = new String(txt.getBytes("iso-8859"),"utf-8");
		out.print("txt="+txt+Math.random());
		out.flush();
		out.close();
	}

	/**
	 * The doPost method of the servlet. 

	 *
	 * This method is called when a form has its tag value method equals to post.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		
		request.setCharacterEncoding("utf-8");
		response.setContentType("text/html;charset=UTF-8");
		PrintWriter out = response.getWriter();
		String username = request.getParameter("username");
//		String txt = new String(username.getBytes("ISO-8859-1"),"UTF-8");
		String txt = new String(username);
		out.print("txt="+txt+":"+Math.random());
		
		out.flush();
		out.close();
	}