date_select

Get year to show in descending order (Today to 1920 for example)

The way people think of time start and end would be 1920 to today. This made me think “but I want it show the current year first then down.” Well it’s as simple as swapping the start_year and end_year.

date_select :date, :start_year => Date.current.year, :end_year => 1920

# => 2008, 2007, 2006, 2005 ... 1920

Disable default date

If you want a date selector that initially doesn’t have a date selected you can pass it the option :include_blank.

date_select("project", "due_date", :include_blank => true)

Date_select with assert_valid_keys

If you are using date_select with assert_valid_keys you have to allow 3 parameters named field(1i), field(2i) and field(3i).

For example with field

date_select("post", "written_on")

You have to allow following fields:

params[:post].assert_valid_keys( 
  'written_on(1i)', 'written_on(2i)', 'written_on(3i)'
)

end_year

date_select supports end_year, too.

date_select("user", "birthday", :start_year => 1940, :end_year => Date.current.year - 13)

All dates in the database are stored in UTC and all dates in Ruby are in a local timezone

With the timezone support introduced in Rails 2.1 the idea is that all dates in the database are stored in UTC and all dates in Ruby are in a local timezone.

Time.zone.now == Time.now # => false

as Peter Marklund lights up this in his blog:

http://marklunds.com/articles/one/402

“They will only be converted to UTC for you if they are ActiveSupport::TimeWithZone objects, not if they are Time objects. This means that you are fine if you use Time.zone.now, 1.days.ago, or Time.parse(”2008-12-23“).utc, but not if you use Time.now or Time.parse(”2008-12-23“)”

Passing html options (Ruby hash parameters)

When you have two default hash parameters at the end of a function call, you need to use it as the following:

options = { :include_blank => true, :default => @my_object.my_method }

date_select :my_object, :my_method, options, :class => 'my_css_class'

You can try it for yourself on this example:

def test_funct a = {}, b = {}
  puts "a: #{a.inspect}"
  puts "b: #{b.inspect}"
end

test_funct :x => 'x', :y => 'y'  # all the parameters are collected for the hash a

Parsing the Date Params into a New Date Object.

Useful for when you need to create a Date object from these manually, such as for reporting.

If the date select input is start_date and it belongs to the report form object:

@start_date = Date.civil(params[:report]["start_date(1i)"].to_i,
                         params[:report]["start_date(2i)"].to_i,
                         params[:report]["start_date(3i)"].to_i)

@start_date.class
# => Date

@start_date
# => Sun, 25 Sep 2011  # For example.

Use a similar method for DateTime situations.

Incorrectly named option

The :add_month_number option should be :add_month_numbers

rails date_select examples

I have combined some of the tips here: http://www.rubyplus.net/2016/11/rails-dateselect-examples.html

Locale

To change default locale by the parameter you can set :locale option, like below:

select_date 'user', 'birth', :locale => 'de'

Default field order

If you want to set an app wide default order for the fields (rather than passing :order each time), use the locale file.

eg. edit config/locale/en.yml to include:

en:
  date:
    order: 
      - :day
      - :month
      - :year

:discard_month implicitly sets :discard_day to true

This may not be the behaviour that you want, and setting :discard_day => false doesn’t change this. One way of getting around this is to hide the month field using CSS e.g.

#some_date_field_2i {
  display:none;
}

If you use the :default option for the date_select, the correct default month will be passed through to the controller. Using this with :discard_year will give you a dropdown with only the day, but preserve the month and year as provided by :default.