AngularJs: server side username and password validation -

i new angularjs , trying write code login validation.following code check whether typed username , password correct or not. how can display "invalid username" , "invalid password" message when username or password not correct after pressing login button?i want display error messages instead of using alert.thank you.

<script>         var app=angular.module("app",[]);         app.controller("mainctrl",function($scope,$http,$window) {         $scope.checklogin = function(result) {             //$http.get("login.jsp")                           $http.get("login.jsp?sqlstr=select usrnm,usrpwd dbo.tblusr usrnm = '" + $scope.user_name + "'")             .success(function(response) {                 $scope.mydata = response;                 if(!angular.isobject($scope.mydata[0]))                                                 alert("invalid user name");                  else                 {                     if($scope.mydata[0].usrpwd!== $scope.password)                         alert("invalid password");                     else                         //alert("successfully logged in");                         $window.location.href = 'mainpage.html';                 }             })             .error(function(){                 alert("resource not found");              });             };         });     </script> 

something work:

<script>     var app=angular.module("app",[]);     app.controller("mainctrl",function($scope,$http,$window) {     $scope.checklogin = function(result) {         //$http.get("login.jsp")                       $http.get("login.jsp?sqlstr=select usrnm,usrpwd dbo.tblusr usrnm = '" + $scope.user_name + "'")         .success(function(response) {             $scope.mydata = response;             if(!angular.isobject($scope.mydata[0]))                                             alert("invalid user name");              else             {                 if($scope.mydata[0].usrpwd!== $scope.password)                     alert("invalid password");                     $scope.haserror = true;                     $scope.errortext = "invalid password";                 else                     //alert("successfully logged in");                     $window.location.href = 'mainpage.html';                     $scope.haserror = false;                     $scope.errortext = "";             }         })         .error(function(){             alert("resource not found");             $scope.haserror = true;         });         };     }); 

and in html:

<div ng-show="haserror">{{errortext}}</div> 

edit- bad way validate passwords, looks you're passing password server. don't that, it's very, insecure. should validate hash on server, , pass authorization or rejection client. also, if you're transmitting passwords in plain text @ point, sure you're using ssl.