预订中的NoMethodError＃index未定义的方法`strftime'为零：NilClass

我是在Windows上使用rails和running rails 4的新手。我几天来一直在处理这个错误。我认为我输入的以前的数据可能有问题，所以我尝试在控制台中创建一个新的预留，以查看发生了什么问题，但目前为止没有运气。预订中的NoMethodError＃index未定义的方法`strftime'为零：NilClass

这是我的用户模型：

class User < ActiveRecord::Base 
devise :database_authenticatable, :registerable, :recoverable, :rememberable, :trackable, :validatable 

    attr_accessible :name, :email, :password, :remember_me 

    has_many :reservations 
end

预订模型：

class Reservation < ActiveRecord::Base 

    attr_accessible :user_id, :user_name, :start_time, :end_time, :project, :which_room 

end

预订指数：

<tbody> 
    <% @reservations.each do |reservation| %> 
    <tr> 
     <td><%= current_user.name %></td> 
     <td><%= reservation.project %></td> 
     <td><%= reservation.start_time.strftime("%I:%M %p")%></td> 
     <td><%= reservation.end_time.strftime("%I:%M %p")%></td> 
     <td><%= reservation.which_room %></td> 
     <td><%= link_to 'Edit', edit_reservation_path(reservation) %></td> 
     <td><%= link_to 'Destroy', reservation, method: :delete, data: { confirm: 'Are you sure?' } %></td> 
    </tr> 
    <% end %> 
</tbody> 
    </table> 
</div>

显示操作：

<p> 
<strong>User:</strong> 
<%= @user.name %> 
</p> 

<p> 
<strong>Project:</strong> 
<%= @reservation.project %> 
</p> 

<p> 
<strong>Start time:</strong> 
<%= @reservation.start_time %> 
</p> 

<p> 
<strong>End time:</strong> 
<%= @reservation.end_time %> 
</p> 

<p> 
<strong>Room number:</strong> 
<%= @reservation.which_room %> 
</p>

和保留控制器：类ReservationsController <的ApplicationController before_action：set_reservation，只有：[：显示，编辑，：更新：摧毁]

def index 
    @reservations = Reservation.all.order(which_room: :asc, start_time: :desc) 
end 

def show 
end 

def new 
    @reservation = Reservation.new 
end 

def edit 
end 

def create 
    @reservation = Reservation.new(reservation_params) 

respond_to do |format| 
    if @reservation.save 
    format.html { redirect_to @reservation, notice: 'Reservation was successfully created.' } 
    format.json { render action: 'show', status: :created, location: @reservation } 
    else 
     format.html { render action: 'new' } 
     format.json { render json: @reservation.errors, status: :unprocessable_entity } 
    end 
    end 
end 

def update 
    respond_to do |format| 
    if @reservation.update(reservation_params) 
     format.html { redirect_to @reservation, notice: 'Reservation was successfully updated.' } 
     format.json { head :no_content } 
    else 
    format.html { render action: 'edit' } 
    format.json { render json: @reservation.errors, status: :unprocessable_entity } 
    end 
    end 
end 

def destroy 
    @reservation.destroy 
    respond_to do |format| 
    format.html { redirect_to reservations_url } 
    format.json { head :no_content } 
    end 
end 

private 
    def set_reservation 
    @reservation = Reservation.find(params[:id]) 
end 

def reservation_params 
    params.require(:reservation).permit(:project, :start_time, :end_time, :which_room) 
end 
end

TIA！

来源

2014-11-06 eatsleepcode