Use of Ajax in jquery (Java)

Ajax Way

JS: interface

var prjcontextpath= ' <%=request.getcontextpath ()%> ';

$ (document). Ready (function(){     //===============get==============================$ ("#username"). Blur (function() {$.ajax ({type:"GET", Url:prjcontextpath+ "/zhuceaction!queryusername.action?username=" + $ ("#username"). Val () + "&pwd=" +$ ("#pwd"). Val (), DataType:"JSON", Success:function(data) {if(data.success) {$ ("#usernamemsg"). HTML ("<font color= ' green ' >" + data.msg + "</font>"); } Else {                    $("#usernamemsg"). HTML ("<font color= ' Red ' >" + data.msg + "</font>"); }}, Error:function(JQXHR) {alert ("Error occurred:" +jqxhr.status);    }             });      }); //===============post==============================$ ("#username"). Blur (function() {$.ajax ({type:"POST", Url:prjcontextpath+ "/zhuceaction!queryusername.action", Data: {username: $ ("#username"). Val (), PWD: $ ("#pwd"). Val ()}, DataType:"JSON", Success:function(data) {if(data.success) {$ ("#usernamemsg"). HTML ("<font color= ' green ' >" + data.msg + "</font>"); } Else {                     $("#usernamemsg"). HTML ("<font color= ' Red ' >" + data.msg + "</font>"); }}, Error:function(JQXHR) {alert ("Error occurred:" +jqxhr.status);    }            }); });});

Call the method in the action:

Note: This action inherits Baseaction

 Public voidQueryusername ()throwsIOException {System.out.println ("Username=" +user.getusername ()); System.out.println ("Pwd=" +user.getpwd ()); //go to the database to verify        BooleanFlag =true; //form a JSON stringString html = ""; if(flag) {HTML= "{\" success\ ": 1,\" msg\ ": \" username, can be used! \"}"; } Else{html= "{\" success\ ": 0,\" msg\ ": \" username, not available! \"}"; }        //call a method in Baseaction to write a JSON string to the output streamResponsewriterjson (HTML); }

baseaction Code:

 PackageAction;Importjava.io.IOException;ImportJava.io.PrintWriter;ImportJavax.servlet.http.HttpServletResponse;ImportOrg.apache.struts2.ServletActionContext; Public classbaseaction { Publichttpservletresponse response; /*** Back to page data *@paramreturnstring Return Data *@throwsIOException Exception*/     Public voidResponsewriterjson (String returnstring)throwsIOException {Response=Servletactioncontext.getresponse (); Response.setcontenttype ("Application/json;charset=utf-8");            Response.getwriter (). write (returnstring);            Response.flushbuffer ();             Response.getwriter (). Close (); }    /*** Return page XML data *@paramreturnstring Return Data *@throwsIOException Exception*/     Public voidResponsewriterxml (String returnstring)throwsIOException {Response=Servletactioncontext.getresponse (); Response.setcharacterencoding ("Utf-8"); Response.setcontenttype ("Text/xml"); Response.setheader ("Cache-control", "No-cache");            Response.getwriter (). write (returnstring);            Response.flushbuffer ();            Response.getwriter (). Close (); }    /*** Back to page data *@paramreturnstring *@throwsIOException Exception*/     Public voidPrintWriter (String returnstring)throwsIOException {Response=Servletactioncontext.getresponse (); Response.setcontenttype ("Text/html;charset=utf-8"); PrintWriter out=Response.getwriter ();            Out.println (returnstring);            Out.close (); }    }

Post mode

Js:

//-----------Query the user name start-------------------------------------------$ (document). Ready (function() {query (); });//-----------Query the user name end-------------------------------------------//Load query Land registration approval form (judge: Add/update/search)functionquery () {varUsername = "AA"; varPWD = "BB"; $.post (Prjcontextpath+ "/updateaction!query.action", {username:username,pwd:pwd},callbackquerysuccess);}functioncallbackquerysuccess (JSON) {if(Json.data! =NULL|| Json.data! = "")    {        //Assigning a value to a page        /** Method 1 for (Var i=0;i<json.data.length;i++) {var tbbody = "";            var trcolor= "";            Alert ("i=" +i);                        var editdata=json.data[i];            if (i% 2 = = 0) {Trcolor = "even";            } else {trcolor = "odd"; } Tbbody + = "<tr class=" + trcolor + "><td>" + editdata.name + "</td>" + "<td>" + EDI            Tdata.age + "</td></tr>";        $ ("#myTb"). Append (Tbbody); }        */                        //Assigning a value to a page Method 2         varTypedata =Json.data; $.each (Typedata,function(i, n) {varTbbody = ""varTrcolor; if(i% 2 = = 0) {Trcolor= "even"; }            Else{Trcolor= "Odd"; } tbbody+ = "<tr class=" + trcolor + "><td>" + n.name + "</td>" + "<td>" + n.age + "</td>" + "<t D> "+ n.like[0" + "</td></tr>"; $("#myTb"). Append (Tbbody);            }); }}

Action

 PackageAction;Importjava.io.IOException;Importjava.util.ArrayList;Importjava.util.List;ImportBean. User;ImportBean. UserInfo;ImportCom.alibaba.fastjson.JSON;ImportCom.opensymphony.xwork2.ModelDriven; Public classUpdateactionextendsBaseactionImplementsModeldriven<user>{User User=NewUser ();  PublicUser Getmodel () {returnuser; }     Public voidQuery ()throwsIOException {System.out.println ("Username=" +user.getusername ()); System.out.println ("Pwd=" +user.getpwd ()); UserInfo UserInfo=NewUserInfo (); Userinfo.setname ("Zhang San"); Userinfo.setage (20); Userinfo.setbirthday ("1990-10-09"); String[] Likes=NewString[] {"Basketball", "football" };        Userinfo.setlike (likes); Userinfo.sethasgirlfirend (false); Userinfo.setcar (NULL); UserInfo Userinfo2=NewUserInfo (); Userinfo2.setname ("John Doe"); Userinfo2.setage (20); Userinfo2.setbirthday ("1991-11-11"); String[] Likes1=NewString[] {"Billiards", "Badminton" };        Userinfo2.setlike (LIKES1); Userinfo2.sethasgirlfirend (false); Userinfo2.setcar (NULL); List<UserInfo> userjsonlist =NewArraylist<userinfo>();        Userjsonlist.add (userinfo);        Userjsonlist.add (Userinfo2); String Jsonarray=json.tojsonstring (userjsonlist); StringBuffer responsestring=NewStringBuffer (); Responsestring.append ("{\" total\ ":"). Append (2). Append (", \" data\ ":"). Append (Jsonarray). Append ("}");        System.out.println (Responsestring.tostring ()); //call a method in Baseaction to write a JSON string to the output streamResponsewriterjson (responsestring.tostring ()); /**{"Total": 2, "data": [{"Age": "Birthday": "1990-10-09", "Hasgirlfirend": false , "like": ["basketball", "football"], "name": "31"}, {"Age": "Birthday": "1990-10-09", "have Girlfirend ": false," like ": [" basketball "," soccer "]," name ":" Zhang San "}]}*/        }}

Use of Ajax in jquery (Java)