building an array of dates

rubyonrails-talk
1

I need to build an array that contains lots of date objects.

I've got a booking model and it contains stuff like this...

  create_table "bookings", :force => true do |t|     t.string "firstname"     t.string "lastname"     t.integer "number_of_people"     t.integer "deposit"     t.integer "price"     t.integer "days"     t.datetime "from"     t.datetime "to"     t.datetime "created_at"     t.datetime "updated_at"   end

SOO - each booking starts on a date and finishes on a date...

I need to collect up all the booking dates in an array so that I can do stuff with them...

I figure i need a method in my model to do it...

something like

  def self.all_booking_dates

    find(:all); # first off find all the booking records

    @BookedDays = ( XXX ).map # do something here to create an array with all the dates in, maybe I need a loop ... sorry bit stuck?

  end

be grateful for any tips.

thanks...

2

bingo bob wrote:

I need to collect up all the booking dates in an array so that I can do stuff with them...

I figure i need a method in my model to do it...

something like

  def self.all_booking_dates

    find(:all); # first off find all the booking records

    @BookedDays = ( XXX ).map # do something here to create an array with all the dates in, maybe I need a loop ... sorry bit stuck?

  end

To get an array of dates for just one booking, you can build a range and then convert it to an array:

(from..to).to_a

To get the array of dates for a set of bookings (such as all bookings), I think something like this is what you're looking for:

bookings.map { |b| (b.from..b.to).to_a }.flatten.uniq.sort

3

Thanks, I'll try that.

I got to here myself, but it's not right ! I think it's close though and I find this syntax easier to read.

def availability

  @bookings = Booking.find(:all)

  for booking in @bookings do     bookingfirstday = booking.from.to_date     bookinglastday = booking.to.to_date     @BookedDays = (bookingfirstday..bookinglastday).map   end

end

Can you explain why it's wrong ?

The result is that I @BookedDays only gets set to the last evaluated booking (I think).

I will try your way though, thanks. (I'd like to get my way working also if poss)?

Is the loop rewriting @BookedDays each time around rather than adding to it?

ta

4

bingo bob wrote:

Thanks, I'll try that.

I got to here myself, but it's not right ! I think it's close though and I find this syntax easier to read.

def availability

  @bookings = Booking.find(:all)

  for booking in @bookings do     bookingfirstday = booking.from.to_date     bookinglastday = booking.to.to_date     @BookedDays = (bookingfirstday..bookinglastday).map   end

end

Can you explain why it's wrong ?

The result is that I @BookedDays only gets set to the last evaluated booking (I think).

I will try your way though, thanks. (I'd like to get my way working also if poss)?

Is the loop rewriting @BookedDays each time around rather than adding to it?

ta

There are a couple problems. The first is that, yes, @BookedDays is being rewritten, not appended to. You need to initialize the array before the loop starts (@BookedDays = ) and use the += method to append to it. Also, you should renamed that variable to @booked_days. You can do this with a for-loop, but I suggest getting used to the closured-oriented methods in Enumerable and Array. Your code will be much more concise and expressive.

5

Thanks that's very clear and helpful, I'll try and use the more concise method.

It's working for me and I understand why my version wasn't.

Maybe my brain is squished but I've done the hard thing and now this next more simple loop is causing me problems in my view. I wish to show 12 calendars from the current month to 12 months on.

So I know how to display one....<working>

<%= calendar(:year => 2009, :month => 1) do |d|

    if @BookedDays.include?(d)       [d.mday, {:class => "specialDay"}]     else       [d.mday, {:class => "normalDay"}]     end

end

%>

How do I display twelve of em...I know this is uber easy but I can't get it to work.

I firgure something like what follows is useful but I cant get the loop within the loop working in the view.

<% start = Time.now.month finish = Time.now.month + 12 %>

6

bingo bob wrote:

How do I display twelve of em...I know this is uber easy but I can't get it to work.

I firgure something like what follows is useful but I cant get the loop within the loop working in the view.

<% start = Time.now.month finish = Time.now.month + 12 %>

Yeah, that's not going to work. The easiest way is probably something like this:

<% d = Date.today %> <% 12.times do %>

  <%= calendar(:year => d.year, :month => d.month) do |d|     if @BookedDays.include?(d)       [d.mday, {:class => "specialDay"}]     else       [d.mday, {:class => "normalDay"}]     end   end   %>

<% d >>= 1 # advance 1 month %> <% end %>

7

Small critique here on your code style. @BookedDays doesn't really follow Ruby on Rails conventions. Camel-case should only be used by class/module definitions and references. @booked_days is the convention that Rails encourages.

This might be something that you've decided based on a personal or team preference, but in case you're not attached to it, following Rails conventions will make your life and anybody else that later works on a project.. a little easier. :slight_smile:

Cheers, Robby