Ruby-on-rails 未定义的方法每个 rails 错误
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undefined method each rails error
提问by Micheal
I was trying out ruby on rails through the tutorial located at http://ruby.railstutorial.org. I got to to the point where I could create users and have their name and gravatar displayed at:
我正在通过http://ruby.railstutorial.org上的教程尝试使用 ruby on rails 。我已经到了可以创建用户并在以下位置显示他们的姓名和头像的地步：
http://localhost:3000/users/1
Now I want to display all users when a user goes to:
现在我想在用户访问时显示所有用户：
http://localhost:3000/users/
Here is my controller:
这是我的控制器：
class UsersController < ApplicationController
def index
@user = User.all
end
#...
end
Here is my view.
这是我的看法。
#View for index action in user's controleer
<h1>All users</h1>
<ul class="users">
<% @users.each do |user| %>
<li><%= user.content %></li>
<% end %>
</ul>
I get the following error.
我收到以下错误。
undefined method `each' for nil:NilClass
Can someone tell me why the index page is not working as I want it to.
有人能告诉我为什么索引页没有按我想要的那样工作。
回答by MrYoshiji
The problem comes from the @usersvariable that does not exists:
问题来自@users不存在的变量：
In your index action you set @userto all users:
在您@user为所有用户设置的索引操作中：
def index
@user = User.all
end
By convention, we use pluralized names when we retrieve several entries from the DB, that's why you are calling @users(notice the 's') in the view. Just rename your @userto @usersand it will be okay ;)
按照惯例，当我们从数据库中检索多个条目时，我们使用复数名称，这就是您@users在视图中调用（注意“s”）的原因。只需将您的名称重命名@user为@users，就可以了 ;)
def index
@users = User.all
end
