Convert Hash to Object

Ruby: Convert nested hash to object?

You need to add recursivity:

class Hashit
  def initialize(hash)
    hash.each do |k,v|
      self.instance_variable_set("@#{k}", v.is_a?(Hash) ? Hashit.new(v) : v)
      self.class.send(:define_method, k, proc{self.instance_variable_get("@#{k}")})
      self.class.send(:define_method, "#{k}=", proc{|v| self.instance_variable_set("@#{k}", v)})
    end
  end
end

h = Hashit.new({a: '123r', b: {c: 'sdvs'}})
# => #<Hashit:0x007fa6029f4f70 @a="123r", @b=#<Hashit:0x007fa6029f4d18 @c="sdvs">>

Convert Hash to OpenStruct recursively

personally I use the recursive-open-struct gem - it's then as simple as RecursiveOpenStruct.new(<nested_hash>)

But for the sake of recursion practice, I'll show you a fresh solution:

require 'ostruct'

def to_recursive_ostruct(hash)
  result = hash.each_with_object({}) do |(key, val), memo|
    memo[key] = val.is_a?(Hash) ? to_recursive_ostruct(val) : val
  end
  OpenStruct.new(result)
end

puts to_recursive_ostruct(a: { b: 1}).a.b
# => 1

edit

Weihang Jian showed a slight improvement to this here https://stackoverflow.com/a/69311716/2981429

def to_recursive_ostruct(hash)
  hash.each_with_object(OpenStruct.new) do |(key, val), memo|
    memo[key] = val.is_a?(Hash) ? to_recursive_ostruct(val) : val
  end
end

Also see https://stackoverflow.com/a/63264908/2981429 which shows how to handle arrays

note

the reason this is better than the JSON-based solutions is because you can lose some data when you convert to JSON. For example if you convert a Time object to JSON and then parse it, it will be a string. There are many other examples of this:

class Foo; end
JSON.parse({obj: Foo.new}.to_json)["obj"]
# => "#<Foo:0x00007fc8720198b0>"

yeah ... not super useful. You've completely lost your reference to the actual instance.

Ruby: Convert nested hash to object?

You need to add recursivity:

class Hashit
  def initialize(hash)
    hash.each do |k,v|
      self.instance_variable_set("@#{k}", v.is_a?(Hash) ? Hashit.new(v) : v)
      self.class.send(:define_method, k, proc{self.instance_variable_get("@#{k}")})
      self.class.send(:define_method, "#{k}=", proc{|v| self.instance_variable_set("@#{k}", v)})
    end
  end
end

h = Hashit.new({a: '123r', b: {c: 'sdvs'}})
# => #<Hashit:0x007fa6029f4f70 @a="123r", @b=#<Hashit:0x007fa6029f4d18 @c="sdvs">>

How to convert a hash to a single object in JavaScript?

If you just want to use a loop, you can do it like this :

var log = [  {    billkey: "Name",    billvalue: "ABC"  },  {    billkey: "Department",    billvalue: "Computer"  }];  var result = {};  log.forEach(x => result[x.billkey] = x.billvalue);  console.log(result);

converting a hash string into a date object ruby

Handle Both Standard and Custom Date Strings

Date#parse doesn't handle arbitrary strings in all cases. Even when it does, it may not handle them the way you expect. For example:

parse_date "1/1/18"
#=> #<Date: 2001-01-18 ((2451928j,0s,0n),+0s,2299161j)>

While Date#parse handles many date formats automagically, it only successfully parses objects that match its internal expectations. When you have multiple or arbitrary date formats, you have to define your own date specifications using Date#strptime to handle those formats that Date#parse doesn't understand, or that it handles incorrectly. For example:

require 'date'

def parse_date str
  Date.parse str
rescue Date::Error
  case str
  when /\A\d{4}\z/
    Date.strptime str, '%Y'
  when /\A\d{2}\z/
    Date.strptime str, '%y'
  else
    raise "unexpected date format: #{str}"
  end
end

date_samples = ["July 11th 1960", "September 1988", "1776"]

date_samples.map { |date| parse_date(date) }
#=> [#<Date: 1960-07-11 ((2437127j,0s,0n),+0s,2299161j)>, #<Date: 1988-09-01 ((2447406j,0s,0n),+0s,2299161j)>, #<Date: 1776-01-01 ((2369731j,0s,0n),+0s,2299161j)>]

This obviously is not an exhaustive list of potential formats, but you can add more examples to date_samples and update the case statement to include any unambiguous date formats you expect from your data set.

How do I convert a String object into a Hash object?

The string created by calling Hash#inspect can be turned back into a hash by calling eval on it. However, this requires the same to be true of all of the objects in the hash.

If I start with the hash {:a => Object.new}, then its string representation is "{:a=>#<Object:0x7f66b65cf4d0>}", and I can't use eval to turn it back into a hash because #<Object:0x7f66b65cf4d0> isn't valid Ruby syntax.

However, if all that's in the hash is strings, symbols, numbers, and arrays, it should work, because those have string representations that are valid Ruby syntax.

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