Ruby-on-rails 从 Rails 中的 ActiveRecord::RecordNotFound 救援
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rescue from ActiveRecord::RecordNotFound in Rails
提问by Adnan
A user can only edit its own post, so I use the following to check if a user can enter the edit form:
用户只能编辑自己的帖子，因此我使用以下内容来检查用户是否可以输入编辑表单：
def edit
@post = Load.find(:first, :conditions => { :user_id => session[:user_id], :id => params[:id]})
rescue ActiveRecord::RecordNotFound
flash[:notice] = "Wrong post it"
redirect_to :action => 'index'
end
But it is not working, any ideas what I am doing wrong?
但它不起作用，任何想法我做错了什么？
回答by Simone Carletti
If you want to use the rescue statement you need to use find()in a way it raises exceptions, that is, passing the id you want to find.
如果要使用救援语句，则需要以find()引发异常的方式使用，即传递要查找的 id。
def edit
@post = Load.scoped_by_user_id(session[:user_id]).find(params[:id])
rescue ActiveRecord::RecordNotFound
flash[:notice] = "Wrong post it"
redirect_to :action => 'index'
end
回答by Tim Baas
You can also use ActionController's rescue_frommethod. To do it for the whole application at once!
您也可以使用ActionController的rescue_from方法。一次为整个应用程序做这件事！
class ApplicationController < ActionController::Base
rescue_from ActiveRecord::RecordNotFound, :with => :record_not_found
def record_not_found
render 'record_not_found' # Assuming you have a template named 'record_not_found'
end
end
回答by EmFi
Turns out you were using rescue and find(:first) incorrectly.
原来你错误地使用了rescue和find(:first)。
find :first returns nil if no record matches the conditions. It doesn't raise ActiveRecord::RecordNotFound
find :first 如果没有符合条件的记录返回 nil。它不会引发 ActiveRecord::RecordNotFound
try
尝试
def edit
@post = Load.find(:first, :conditions => { :user_id => session[:user_id], :id => params[:id]})
if @post.nil?
flash[:notice] = "Wrong post it"
redirect_to :action => 'index'
end
end
