Ajax很简单(jsp例子)
首先是jsp页面和脚本为了方便写在一个里面
这是一个很常见的检测用户名是否存在的功能
这里用的是struts 可以在路径path中加加上要传的值name 在action中连接数据库 验证是否存在
<%@ page contentType=text/html; charset=GBK %>
<html>
<head>
<title>
ajax
</title>
</head>
<body bgcolor=#ffffff>
<h>
<input name=username type=text maxlength= />
<input id=chknamebtn type=button value=检测帐号 onclick=testName(<%=requestgetContextPath()%>) />
<div id=view_name></div>
</h>
</body>
</html>
<script language=javascript>
if (windowActiveXObject && !windowXMLHttpRequest) {
windowXMLHttpRequest=function() {
return new ActiveXObject((navigatoruserAgenttoLowerCase()indexOf(msie ) != ) ? MicrosoftXMLHTTP : MsxmlXMLHTTP);
};
}//取得XMLHttpRequest对象
function testName(path){
//path是取得系统路径
var view_name=documentgetElementById(view_name);
var req=new XMLHttpRequest();
if (req) {
reqonreadystatechange=function() {
if (reqreadyState== && reqstatus==) {//判断状态是已发送已完成
if(reqresponseText==){
lor=green;
view_nameinnerHTML=该用户名可以正常使用;
}else if(reqresponseText==){
lor=red;
view_nameinnerHTML=该用户名已经被使用;
}else{
lor=red;
view_nameinnerHTML=该用户名含有非法字符！;
}
}
}
reqopen(POST path+/ajaxdo);//struts
//reqopen(POST path+/ajaxservlet);//servlet
//reqopen(POST path+/ajaxaction);//webwork
reqsetRequestHeader(ContentType application/xwwwformurlencoded);
reqsend();//发送参数如果有参数reqsend(username=+user_name);用request取得
}
}
</script>
这个jsp页面并没有取得用户名就是演示一下还有<div>可以换span具体作用问美工吧
接受ajax请求的action
import orgapachestrutsaction*;
import javaxservlethttp*;
import javaxservlethttpHttpServlet;
import javaxservlethttpHttpServletRequest;
import javaxservlethttpHttpServletResponse;
import javaioPrintWriter;
/**
* <p>Title:AjaxAction </p>
*/
public class AjaxAction extends Action {
public ActionForward execute(ActionMapping mapping
ActionForm form
HttpServletRequest request
HttpServletResponse response)
throws Exception {
PrintWriter out = responsegetWriter();
outprint();//ajax取得都是字符的输出如果数据量大的话还可以用xml来发送和接受
return null;
}
}
strutsconfigxml
<action type=testwhwuploadAjaxAction validate=false scope=request path=/ajax/>
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如果是servlet
webxml
<servlet>
<servletname>AjaxServlet </servletname>
<servletclass>servletAjaxServlet </servletclass>
</servlet>
<servletmapping>
<servletname>AjaxServlet </servletname>
<urlpattern>/AjaxServlet servlet</urlpattern>
</servletmapping>
AjaxServletjava
import javaioIOException;
import javaioPrintWriter;
import javaxservletServletException;
import javaxservlethttpHttpServlet;
import javaxservlethttpHttpServletRequest;
import javaxservlethttpHttpServletResponse;
public class AjaxServlet extends HttpServlet {
Logger log = LoggergetLogger(thisgetClass());
public void doGet(HttpServletRequest request HttpServletResponse response)
throws ServletExceptionIOException {
responsesetContentType(text/xml; charset=GBK);
PrintWriter out = responsegetWriter();
outprint();
}
}
//Process the HTTP Post request
public void doPost(HttpServletRequest request HttpServletResponse response)
throws ServletException IOException {
doGet(request response);
}
//Process the HTTP Put request
public void doPut(HttpServletRequest request HttpServletResponse response)
throws ServletException IOException {
}
//Process the HTTP Delete request
public void doDelete(HttpServletRequest request
HttpServletResponse response) throws ServletException IOException {
}
//Clean up resources
public void destroy() {
}
}
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如果是webwork
xworkxml
<action name=ajax class=comwhwuploadactionwebworkAjaxAction method=ajax/>
AjaxActionjava
import javaioPrintWriter;
public class AjexAlbumAction extends ActionSupport implements Action{
public void ajax()throws IOException {
PrintWriter pw = ServletActionContextgetResponse()getWriter();
ServletActionContextgetResponse()setContentType(text/html;charset=GBK);
pwprint();
pwclose();
}
}
