How to Pass ActiveRecord Objects as Parameters to Helper Methods in Rails -


For many support methods, such as redirect_to, link_to, and url_, instead of a hash, an ActiveRecord object It can take control and specifies the action I have seen that the parameters have passed different documents in different ways. It is sometimes passed as a symbol, sometimes in the form of an example variable, and sometimes as a local variable

I am confused about how to alter the various parameters styles to return the URL. I know that at the following conventions, a controller and action should be made to create the URL, but it is uncertain that when the railroad requires a specific parameter style for the construction of that URL. Please help me understand the usage cases to pass the ActiveRecord object as an icon, an instance variable, or a local variable. Do the methods have different requirements depending on the call? Or is there a difference in the URL creation?

Here are some examples:

From API docs: 

  link_to "profile", @profile redirect_to post  & Lt;% = form_for: Making a Person | F | & Gt%; (This is described as "normal") from Ruby on Rail Guides:  
  & lt;% = Link_to 'new book', new_book_path% & gt; Redirect_to (@ book) for form_for (@article)   
 by railway 3 route:  
  'link_to' "help", help_widgets_path,: popup = & Gt; 1 redirect_to post url_ (timesheets_path) for form_ offer do | F | Note: On further research, it appears that the form_ is able to accept a local variable, where the calling view passes the template: as a local hash parameter The keys are local people that can be partially used and these values ​​are example variables from the template. Is it right to understand?  
 
 
     
  •  You can add objects to link_to and url_for  
  •  Assistant can also pass  
  •  both  @ post  and  posts  items are @ post is a frequency variable, and the post is either a local variables or a The method that will return a post   
     Only "weird" is a  form_for: post  Miscellaneous Rails this old school syntax, and it is under the hood  Form_for @ post  will change to syntax

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