protected void GridView_RowUpdating(object sender, GridViewUpdateEventArgs e)
        {
            Label id = GridView.Rows[e.RowIndex].FindControl("Label_UserId") as Label;

            UserItem                  = TestGit.Core.User.LoadUserByFilters(int.Parse(id.Text));
            Label_Id.Text             = UserItem.UserId.ToString();
            TextBox_FirstName.Text    = UserItem.FirstName;
            TextBox_LastName.Text     = UserItem.LastName;
            TextBox_EmailAddress.Text = UserItem.EmailAddress;

            MultiView_User.SetActiveView(View_Edit);
        }
        protected void LinkButton_User_Command(object sender, CommandEventArgs e)
        {
            switch (e.CommandName)
            {
            case "New":
            {
                UserItem                  = new User();
                Label_Id.Text             = "new user";
                TextBox_FirstName.Text    = null;
                TextBox_LastName.Text     = null;
                TextBox_EmailAddress.Text = null;

                MultiView_User.SetActiveView(View_Edit);
            }
            break;

            case "Update":
            {
                if (int.TryParse(e.CommandArgument.ToString(), out int id))
                {
                    UserItem                  = TestGit.Core.User.LoadUserByFilters(id);
                    Label_Id.Text             = UserItem.UserId.ToString();
                    TextBox_FirstName.Text    = UserItem.FirstName;
                    TextBox_LastName.Text     = UserItem.LastName;
                    TextBox_EmailAddress.Text = UserItem.EmailAddress;

                    MultiView_User.SetActiveView(View_Edit);
                }
            }
            break;

            case "View":
            {
                if (int.TryParse(e.CommandArgument.ToString(), out int id))
                {
                    UserItem                     = TestGit.Core.User.LoadUserByFilters(id);
                    Label_DetailId.Text          = UserItem.UserId.ToString();
                    TextBox_DetailFirstName.Text = UserItem.FirstName;
                    TextBox_DetailLastName.Text  = UserItem.LastName;
                    TextBox_DetailEmail.Text     = UserItem.EmailAddress;

                    MultiView_User.SetActiveView(View_Details);
                }
            }
            break;

            case "Delete":
            {
                if (int.TryParse(e.CommandArgument.ToString(), out int id))
                {
                    TestGit.Core.User.DeleteUser(id);
                    RefreshData();
                    UserItem = null;
                    MultiView_User.SetActiveView(View_Grid);
                }
            }
            break;

            case "Save":
            {
                if (UserItem != null)
                {
                    UserItem.FirstName    = TextBox_FirstName.Text;
                    UserItem.LastName     = TextBox_LastName.Text;
                    UserItem.EmailAddress = TextBox_EmailAddress.Text;
                    UserItem.SaveData();
                    RefreshData();
                    UserItem = null;
                    MultiView_User.SetActiveView(View_Grid);
                }
            }
            break;

            case "Cancel":
            {
                UserItem = null;
                MultiView_User.SetActiveView(View_Grid);
            }
            break;
            }
        }