Hide and Show in angularjs

Question 1

You can use ng-show to hide it

<form ng-show="DisplayUpdate === 'none'" ng-submit="addTodo()">
    <input class="btn-primary" type="submit" value="add">
</form>

If you want to remove it from DOM tree, use ng-if

<form ng-if="DisplayUpdate === 'none'" ng-submit="addTodo()">
    <input class="btn-primary" type="submit" value="add">
</form>

Question 2

Don't set the style directly, use the ng-show directive and let Angular handle it for you.

API Docs

Question 3

Finally i got it .

Below is my code :

JS file :

function TodoCtrl($scope) {

    var value = BindStudentList();
    function BindStudentList() {
        $.ajax({
            url: '/Home/Contact1',
            type: 'GET',
            async: false,
            contentType: 'application/json; charset=utf-8',
            dataType: 'json',
            success: function (data) {
                value = data.data;
            }
        });
        $scope.DisplaySave = true;
        $scope.DisplayUpdate = false;
        return value;
    }

    $scope.addTodo = function () {      
        $.ajax({
            url: '/Home/Index1',
            type: 'GET',
            data: { todoName: $scope.todoName, todoAge: $scope.todoAge },
            contentType: 'application/json; charset=utf-8',
            dataType: 'json',
            success: function (data) {
                value = data.data;
            }
        });
    };

    $scope.Sample = value;
    $scope.remaining = function () {
        var count = 0;
        angular.forEach($scope.Sample, function (todo) {
            count += todo.done ? 0 : 1;
        });
        return count;
    };

    $scope.editTodo = function (Student) {
        $.ajax({
            url: '/Home/Edit1',
            type: 'GET',
            data: { Id: Student.todo.StudentId },
            contentType: 'application/json; charset=utf-8',
            dataType: 'json',
            success: function (data) {
                $scope.todoName = data.data.StudentName;
                $scope.todoAge = data.data.StudentAge;
                $scope.todoId = data.data.StudentId;
                $scope.DisplayUpdate = true;
                $scope.DisplaySave = false;
            }
        });
    };
}

and this is my view code

<!doctype html>
<html ng-app>

<body>
    <script src="~/Scripts/angular.js"></script>

    <h2>Student Details</h2>
    <div ng-controller="TodoCtrl">
        <span>{{remaining()}} of {{Sample.length}} remaining</span>
        [ <a href="" ng-click="archive()">archive</a> ]
        <input type="text" ng-model="todoName" size="30"
            placeholder="Add Your Name">
        <input type="text" ng-model="todoAge" size="30"
            placeholder="Add Your Age">
        <input type="hidden" ng-model="todoId" />
        <form ng-show="DisplaySave" ng-submit="addTodo()">
            <input class="btn-primary" type="submit" value="Save">
        </form>
        <form ng-show="DisplayUpdate" ng-submit="addTodo()">
            <input class="btn-primary" type="submit" value="Update">
        </form>
        <br />
        <br />
        <table>
            <tr>
                <td><b>Student Name</b></td>
                <td><b>Student Age</b></td>
            </tr>
            <tr ng-repeat="todo in Sample">
                <td><span>{{todo.StudentName}}</span></td>
                <td><span>{{todo.StudentAge}}</span></td>
                <td>
                    <button value="{{todo.StudentId}}" ng-click="editTodo(this)">Edit</button>
                </td>
            </tr>
        </table>
    </div>
    <script src="~/Scripts/Todo.js"></script>
</body>
</html>

I added the ng-show="DisplaySave" and ng-show="DisplayUpdate" in my buttons , and i will pass the values like true or false in javascript using angularjs when edit and load time .

Now it's working. I know my code will helps to other person . cheers