-----------------------------------------------------------------------------------------JSP----------------------------- ---------------------------------------------------
<script type= "Text/javascript" src= "/struts2.0/js/jquery-1.11.3.min.js" ></SCRIPT>
<script Type= "Text/javascript";
function Checkusername () {
//Gets the value of the text box
var usernamevalue = $ ("#username"). Val ();
Send request to Server
$.post ("/struts2.0/checkusername", {"username": usernamevalue},function (data) {
//var jsonobject = Eval ("(" +data+ ")");
var html= "";
if (data.flag) {
html= "<font color= ' green ' >" +data.message+ "</font>";
} else{
html= "<font color= ' Red ' >" +data.message+ "</font>";
}
$ ("#username_msg"). HTML (HTML);
}, "json");
}
</script>
<body>
username:<input type= "text" name= "username" id= " Username "onblur=" checkusername () "><span id=" username_msg "></SPAN><BR>
password:< Input type= "password" name= "password" ><BR>
</body>
-----------------------------------------------------------------------------------------Action-------------------------- ------------------------------------------------------
public class Loginaction {
public void Checkusername () {
1. Acceptance of data
String username = servletactioncontext.getrequest (). GetParameter ("username");
Result result = new result ();
2. Determine if username is available
if ("Tom". Equalsignorecase (username)) {
Result.setflag (FALSE);
Result.setmessage ("User name is occupied");
}else{
Result.setflag (TRUE);
Result.setmessage ("User name can be used");
}
Convert result to JSON
String JSON = jsonobject.tojsonstring (result);
try {
Response to Browser via response
Servletactioncontext.getresponse (). setcharacterencoding ("Utf-8");
Servletactioncontext.getresponse (). Getwriter (). write (JSON);
STRTUS2 Framework uses HttpServletResponse response data