Module: Blacklight::HashAsHiddenFieldsHelperBehavior

Included in:
HashAsHiddenFieldsHelper
Defined in:
app/helpers/blacklight/hash_as_hidden_fields_helper_behavior.rb

Overview

Rails Helper methods to take a hash and turn it to form <input type=“hidden”> fields, works with hash nested with other hashes and arrays, standard rails serialization style. Oddly while Hash#to_query will do this for a URL query parameters, there seems to be no built in way to do it to create hidden form fields instead.

Code taken from marklunds.com/articles/one/314

This is used to serialize a complete current query from current params to form fields used for sort and change per-page

Instance Method Summary collapse

Instance Method Details

#flat_hash_key(names) ⇒ Object (protected) 



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# File 'app/helpers/blacklight/hash_as_hidden_fields_helper_behavior.rb', line 51

def flat_hash_key(names)
  names = Array.new(names)
  name = names.shift.to_s.dup 
  names.each do |n|
    name << "[#{n}]"
  end
  name
end

#flatten_hash(hash = params, ancestor_names = []) ⇒ Object (protected) 



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# File 'app/helpers/blacklight/hash_as_hidden_fields_helper_behavior.rb', line 34

def flatten_hash(hash = params, ancestor_names = [])
  flat_hash = {}
  hash.each do |k, v|
    names = Array.new(ancestor_names)
    names << k
    if v.is_a?(Hash)
      flat_hash.merge!(flatten_hash(v, names))
    else
      key = flat_hash_key(names)
      key += "[]" if v.is_a?(Array)
      flat_hash[key] = v
    end
  end
  
  flat_hash
end

#render_hash_as_hidden_fields(hash) ⇒ String

Writes out zero or more <input type=“hidden”> elements, completely representing a hash passed in using Rails-style request parameters for hashes nested with arrays and other hashes.

Parameters:

  • hash (Hash)

Returns:

  • (String) 


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# File 'app/helpers/blacklight/hash_as_hidden_fields_helper_behavior.rb', line 19

def render_hash_as_hidden_fields(hash)
  
  hidden_fields = []
  flatten_hash(hash).each do |name, value|
    value = Array.wrap(value)
    value.each do |v|
      hidden_fields << hidden_field_tag(name, v.to_s, :id => nil)          
    end
  end
  
  safe_join(hidden_fields, "\n")
end