struts1整合ajax技术
1.写一个继承ActionServlet的类A。在该类A中重写HttpServlet的service方法，然后调用ActionServlet中的process方法，然后从requst中得到要返回给前台的值value，如果不为空，则用response. getWriter().print(value);
2.修改web.xml中的名为action的servlet中servlet-class路径为类A的包名+A.
3.在业务Action中把execute方法的返回值设为null,把要返回到前台的对象存放到request中，使类A中的service方法能得到。
4.在写Struts-config.xml文件的action时，不用写forward。
需要下载json-lib包及其相关包。
重写httpServlet中的service方法:
public class ControllerServlet extends ActionServlet{private static final long serialVersionUID = -1967288521493475334L;protected void service(HttpServletRequest arg0, HttpServletResponse arg1) throws ServletException, IOException { //调用ActionServlet 中的process方法 this.process(arg0, arg1); //从request中读取返回给ajax的数据JSONObject JSONObject ajaxResult = (JSONObject)arg0.getAttribute("ajaxResult"); //如果此数据存在，则返回 if(ajaxResult!=null){ arg1.getWriter().print(ajaxResult); }}}public class validataUserAction extends Action{private boolean succ=false; @Override public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) throws Exception { LoginActionForm actionForm=(LoginActionForm)form; //如果username等于kai则设succ为true; if(actionForm.getUsername().equalsIgnoreCase("kai")){ succ=true; } List aa=new ArrayList(); aa.add("kai"); aa.add("haha"); String[] bb = {"aaa","bbb"}; //创建返回的JSONObject对象 JSONObject result = new JSONObject(); result.put("succ", succ); result.put("name", aa); result.put("pass", bb); //把result放到request中，key值必需为ajaxResult request.setAttribute("ajaxResult", result); //一定要返回空值才能使servlet不跳转 return null; }}public class LoginActionForm extends ActionForm{private static final long serialVersionUID = -5121106589990012711L; private String username; private String password; public String getUsername() { return username; } public void setUsername(String username) { this.username = username; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public static long getSerialversionuid() { return serialVersionUID; } }<servlet> <servlet-name>struts1</servlet-name> <servlet-class>com.cronie.struts.ControllerServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>struts1</servlet-name><!--在这我们只对*.aj格式的请求进行ajax处理--> <url-pattern>*.aj</url-pattern></servlet-mapping>
var xmlHttp;function createXmlHttpRequest() {if (window.XmlHttpRequest) { xmlHttp = new XmlHttpRequest();} else if (window.ActiveXObject) { xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");}}function validateUser() {createXmlHttpRequest();xmlHttp.onreadystatechange = handleStateChange;xmlHttp.open("POST", "validataUser.aj", true);xmlHttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded;");var content = "username=" + document.getElementById("username").value;xmlHttp.send(content);}function handleStateChange() {if (xmlHttp.readystate == 4 && xmlHttp.status == 200) { var array; // 把返回结果转化为对象 eval("array=" + xmlHttp.responseText); //alert(array); alert(array.succ); alert(array.name); alert(array.pass);}30}<body> <form action="login.do" method="post"><input name="username" type="text" onblur="validateUser()" id="username"><br><input name="password" type="text"><br><input type="submit" value="submit"><br></form></body>
<struts-config><data-sources /><form-beans> <form-bean name="loginForm" type="com.cronie.struts.LoginActionForm" /></form-beans><global-exceptions /><global-forwards /><action-mappings> <action path="/login" type="com.cronie.struts.Login" name="loginForm" scope="request" validate="false"> <forward name="success" path="/logina.jsp" /> <forward name="error" path="/logina.jsp" /> </action> <action path="/validataUser" type="com.cronie.struts.validataUserAction" name="loginForm" scope="request" validate="false"> </action></action-mappings><message-resources parameter="com.yourcompany.struts.ApplicationResources" /></struts-config>