testAjax.jsp :
<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <html> <head> <Meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>Insert title here</title> <script type="text/javascript"> function ajax(){ var xhr=getXhr(); xhr.onreadystatechange=function(){ if(xhr.readyState==4){ if(xhr.status==200){ document.getElementById("resText").innerHTML=xhr.responseText; } } } xhr.open('get','test',true); xhr.send(null); } function getXhr(){ var xhr=null; if(window.ActiveXObject){ xhr=new ActiveXObject("Microsoft.XMLHTTP"); }else if(window.XMLHttpRequest){ xhr=new XMLHttpRequest(); } return xhr; } </script> </head> <body> <input type="button" value="以ajax方式获取数据" onclick="ajax();"> <div id="resText"></div> </body> </html>TestServlet.java :
public class TestServlet extends HttpServlet {
public void doGet(HttpServletRequest request,HttpServletResponse response)
throws ServletException,IOException {
PrintWriter pw=response.getWriter();
pw.print("hello ajax...");
pw.close();
}
}
为Servlet映射的url为test。
点击按钮后：
如果get方式要传递参数，可以这样：
xhr.open('get','test?name=tom&age=23',true);
public class TestServlet extends HttpServlet {
public void doGet(HttpServletRequest request,IOException {
String name=request.getParameter("name");
String age=request.getParameter("age");
PrintWriter pw=response.getWriter();
pw.print("name:"+name+",age:"+age);
pw.close();
}
} 原文链接：https://www.f2er.com/ajax/165574.html