class User < ActiveRecord::Base
HUMANIZED_ATTRIBUTES = {
:email => "E-mail address"
}
def self.human_attribute_name(attr)
HUMANIZED_ATTRIBUTES[attr.to_sym] || super
end
end
validates_presence_of :song_rep_xyz, :message => "can't be empty"
而在观,而不是离开
@instance.errors.full_messages
当我们使用脚手架生成器时,输入:
@instance.errors.first[1]
您将只得到您在模型中指定的消息,而没有属性名。
解释:
#returns an hash of messages, one element foreach field error, in this particular case would be just one element in the hash:
@instance.errors # => {:song_rep_xyz=>"can't be empty"}
#this returns the first element of the hash as an array like [:key,"value"]
@instance.errors.first # => [:song_rep_xyz, "can't be empty"]
#by doing the following, you are telling ruby to take just the second element of that array, which is the message.
@instance.errors.first[1]
validates_presence_of :email, :message => "Email is required."
但是要像这样显示它
<% if @user.errors.any? %>
<% @user.errors.messages.each do |message| %>
<div class="message"><%= message.last.last.html_safe %></div>
<% end %>
<% end %>
<% if @thing.errors.any? %>
<ul>
<% @thing.errors.full_messages.each do |message| %>
<li><%= message %></li>
<% end %>
</ul>
<% end %>
你可以像这样写你自己的自定义消息:
class Thing < ActiveRecord::Base
validate :custom_validation_method_with_message
def custom_validation_method_with_message
if some_model_attribute.blank?
errors.add(:_, "My custom message")
end
end
object.errors.each do |attr,msg|
if msg.is_a? String
if attr == :base
content_tag :li, msg
elsif msg[0] == "^"
content_tag :li, msg[1..-1]
else
content_tag :li, "#{object.class.human_attribute_name(attr)} #{msg}"
end
end
end
当你想重写错误消息而不带属性名时,只需在消息前面加上^ like:
validates :last_name,
uniqueness: {
scope: [:first_name, :course_id, :user_id],
case_sensitive: false,
message: "^This student has already been registered."
}
#this could be any validation
validates_presence_of :song_rep_xyz, :message => "whatever you want - who cares - we will replace you later"
after_validation :replace_validation_message
def replace_validation_message
custom_value = #any value you would like
errors.messages[:name_of_the_attribute] = ["^This is the replacement message where
you can now add your own dynamic values!!! #{custom_value}"]
end
<% object.errors.each do |attr, msg| %>
<li>
<% case attr.to_sym %>
<% when :song_rep_xyz %>
<%= #display error how you want here %>
<% else %>
<%= object.errors.full_message(attr, msg) %>
<% end %>
</li>
<% end %>