我正在使用 Rails 3.2.9 开发 ROR 应用程序，并且在我的应用程序中收到注册页面的错误消息，如下所示
- <li>登录太短（最少 3 个字符）</li><li>电子邮件太短（最少 7 个字符）</li><li>电子邮件无效</li><li>密码可以 x27;不能为空</li><li>密码太短（最少4个字符）</li><li>密码无效</li><li>密码确认不能为空</li><li>密码无效</li><li>密码确认不能为空</li><li>密码无效</li>李>
这些是 Active Record Validation 的默认消息。（参考： http: //guides.rubyonrails.org/active_record_validations_callbacks.html）
这个应用程序之前是在 Rails 2 中编写的，后来迁移到 rails 3。我已根据 rails 3 将 validates_presence_of 命令更改为 validates : password 、 :presence=>true 等。在视图 (signup.html.erb) 中，error_messages_for 正在呈现这些消息。它已从 rails 3 中弃用。谁能告诉我在视图中需要使用什么而不是 error_messages_for 并且所有代码都需要相应地更改以获取正确的错误消息。
这是代码（不完整）
应用程序/模型中的 user.rb
class User < ActiveRecord::Base
has_many :excel_files # One user may have many excel files
has_one :user_access_validity# One user may have one license period
# Virtual attribute for the unencrypted password
attr_accessor :password
attr_accessible :login
attr_accessible :email
attr_accessible :password
attr_accessible :password_confirmation
attr_accessible :company
#changes of 'validates' in accordance with rails 3:
validates :login, :presence => true,
:length => { :within => 3..40},
:uniqueness => { :case_sensitive => false },
:format => { :with => /^([a-z_0-9\.]+)$/i },
:on => :create,
:if => :is_login_entered?
validates :email, :presence => true,
:length => { :within => 7..100},
:uniqueness => { :case_sensitive => false },
:format => {:with => /^([a-z]+((\.?)|(_?))[a-z0-9]+@(mindtree.com|rvce.edu.in))$/i},
:on => :create,
:if => :is_email_entered?
validates :company, :presence => true,
:format => { :with =>/(mindtree|RVCE)/i},
:format => { :with => /^([a-z]+)$/i },
:on => :create,
:if => :is_company_entered?
#validates_presence_of :login, :email, :company
on => :create, :if => :is_login_entered?
validates :password, :presence => true,
:length => { :within => 4..40 },
:confirmation => true,
:format => { :with => /^([a-z0-9@!#\$]+)$/i },
:on => :create,
:if => :password_required?
validates :password_confirmation, :presence => { :if => :password_required? }
#validates_presence_of :password_confirmation, :if => :password_required?
before_save :encrypt_password
. . .
在 signup.html.erb 中
<font color=red>(Fields marked * are mandatory)</font><h3>Sign me up!</h3>
<br>
<span class='error'><%= error_messages_for (@user) %></span>
<%= form_for :user do |f| -%>
<p><label for="login"><span class='redcolor'>*</span>Login</label><br/>
<%= f.text_field :login %></p>
<p><label for="email"><span class='redcolor'>*</span>Email</label><br/>
<%= f.text_field :email %></p>
<p><label for="password"><span class='redcolor'>*</span>Password</label><br/>
<%= f.password_field :password %></p>
<p><label for="password_confirmation"><span class='redcolor'>*</span>Confirm Password</label><br/>
<%= f.password_field :password_confirmation %></p>
<p><label for="company"><span class='redcolor'>*</span>Company</label><br/>
<%= f.text_field :company %></p>
<p><%= submit_tag 'Sign up' %></p>
<% end -%>
解决方案
从http://www.rubydoc.info/github/edavis10/redmine/ApplicationHelper:error_messages_for获得以下代码 ，应将其添加到 application_helper.rb 和 html.erb 文件中的相应更改为 <%= error_messages_for (@user) % >
代码：
def error_messages_for(*objects)
html = ""
objects = objects.map {|o| o.is_a?(String) ? instance_variable_get("@#{o}") : o}.compact
errors = objects.map {|o| o.errors.full_messages}.flatten
if errors.any?
html << "<div id='errorExplanation'><ul>\n"
errors.each do |error|
html << "<li>#{h error}</li>\n"
end
html << "</ul></div>\n"
end
html.html_safe
end