javascript - Using Validation on Jquery pop up login menu -

i have jquery pop menu using bootstrap . has validation issues when password field empty or password wrong ,i tried couple of ways . works when type in password or username field , still stays there here codes

<div class="container">     <h4>demo page</h4>     <!-- twitter content -->     <div id="form-content" class="modal hide fade in">         <a class="close" data-dismiss="modal">×</a>         <div>             <form class="contact" action="">                 <div class="modal-body">                     <ul class="nav nav-list">                         <li class="nav-header">username</li>                         <li>                             <input class="input-xlarge" type="text" id="txtusername" name="username">                         </li>                         <li class="nav-header">password</li>                         <li>                             <input class="input-xlarge" type="text" id="txtpassword" name="password">                         </li>                     </ul>                 </div>             </form>         </div>         <div class="modal-footer">             <%--<input type="button" value="sign up" id="btnlogin" />--%>             <button class="btn btn-success" id="btnlogin">                 sign             </button>             <a href="#" class="btn" data-dismiss="modal">close</a>         </div>         <div id="dialog" title="message">         </div>     </div> </div> 

and js file has function

function getuserinfo() {     var username = document.getelementbyid('txtusername').value;     var password = document.getelementbyid('txtpassword').value;                if (username == "") {         $('#dialog').text("please type username.");         return false;     }     else if (password == "") {         $('#dialog').text("please type password.");         return false;     }     $.ajax({         url: "webservices/prodmonitorservice.asmx/validateuser",         data: "{'username':'" + username + "','password':'" + password + "'}",         datatype: "json",         type: "post",         contenttype: "application/json; charset=utf-8",         async: true,         success: function (data) {             var obj = jquery.parsejson(data.d);             try {                 if (obj.length == 1) {                     $("#dialog").dialog("close");                 }                 else {                     $('#dialog').text(result.d.message);                     $("#dialog").dialog("open");                 }             }         }); } 

i want display error message when username or password not match and/or blank . use 1 <div id="dialog" title="message"> display error messages based on condition. issue , error message not going away when correct it

any appreciate..

use following code in beginning of getuserinfo function.

$('#dialog').text(""); $("#dialog").dialog("close"); 

for validating username , password, can achieve service side , return status , message success result.

hope helps.

thanks