# Create an array from a hash that includes key and value

**URL:** <https://www.ruby-forum.com/t/create-an-array-from-a-hash-that-includes-key-and-value/143440>\
**Category:** Rails\
**Created:** [July 18, 2008, 5:20pm UTC](https://www.ruby-forum.com/t/create-an-array-from-a-hash-that-includes-key-and-value/143440 "2008-07-18T17:20:12Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![paco.onrails](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/fbc32d/32.png) [@paco.onrails](https://www.ruby-forum.com/u/paco.onrails)\
**Post date:** [July 18, 2008, 5:20pm UTC](https://www.ruby-forum.com/t/create-an-array-from-a-hash-that-includes-key-and-value/143440/1 "2008-07-18T17:20:12Z")

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Hello there, I have the hash:

@hash = {“a”=\>“1”, “b”=\>“2”, “c”=\>“3”}

And I need to create an array:

@array = [[‘a’,‘1’],[‘b’,‘2’],[‘c’,‘3’] ]

How do I do that?

Paco Reyes

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**Author:** ![paco.onrails](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/fbc32d/32.png) [@paco.onrails](https://www.ruby-forum.com/u/paco.onrails)\
**Post date:** [July 18, 2008, 5:34pm UTC](https://www.ruby-forum.com/t/create-an-array-from-a-hash-that-includes-key-and-value/143440/2 "2008-07-18T17:34:15Z")

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@hash.to\_a

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**Author:** ![paco.onrails](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/fbc32d/32.png) [@paco.onrails](https://www.ruby-forum.com/u/paco.onrails)\
**Post date:** [July 18, 2008, 7:05pm UTC](https://www.ruby-forum.com/t/create-an-array-from-a-hash-that-includes-key-and-value/143440/3 "2008-07-18T19:05:02Z")

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Hi –

On Fri, 18 Jul 2008, paco.onrails wrote:

> Hello there, I have the hash:
> 
> @hash = {“a”=\>“1”, “b”=\>“2”, “c”=\>“3”}
> 
> And I need to create an array:
> 
> @array = [[‘a’,‘1’],[‘b’,‘2’],[‘c’,‘3’] ]
> 
> How do I do that?

@hash.to\_a

David

–  
Rails training from David A. Black and Ruby Power and Light:  
Intro to Ruby on Rails July 21-24 Edison, NJ  
Advancing With Rails August 18-21 Edison, NJ  
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<div class="post-metadata">

**Author:** ![paco.onrails](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/fbc32d/32.png) [@paco.onrails](https://www.ruby-forum.com/u/paco.onrails)\
**Post date:** [July 19, 2008, 5:38pm UTC](https://www.ruby-forum.com/t/create-an-array-from-a-hash-that-includes-key-and-value/143440/4 "2008-07-19T17:38:31Z")

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Rob,  
Could I ride this thread with a short variation? I have a zillion  
dropdowns in my project that ask users what code they should choose.  
As a ficticious example they’d be asked what day of the week ( 1 -  
Sunday, 2 - Monday, 3 - Tuesday, etc. )  
I’d like to simply create this as an array and pass it to my  
collection\_select helper. This would save me having to create another  
model and migration.  
What throws me is that the first member of an array has a zero 0 key  
and I want it to be one 1.  
Could someone show me the simple way to load an array with key - value  
combinations that starts with one 1.  
Thank you,  
Kathleen

On Jul 18, 11:55 am, Rob B. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)

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<div class="post-metadata">

**Author:** ![paco.onrails](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/fbc32d/32.png) [@paco.onrails](https://www.ruby-forum.com/u/paco.onrails)\
**Post date:** [July 18, 2008, 7:56pm UTC](https://www.ruby-forum.com/t/create-an-array-from-a-hash-that-includes-key-and-value/143440/5 "2008-07-18T19:56:33Z")

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On Jul 18, 2008, at 11:19 AM, paco.onrails wrote:

> Paco Reyes  
> Either:  
> @array = @hash.to\_a

or:  
@array = @hash.to\_a.sort

depending on whether the order matters. A Hash (in Ruby 1.8.6 and  
earlier) is inherently unordered and the conversion to an array gives  
elements in the same order that @hash.each would yield them.

-Rob

Rob B. [http://agileconsultingllc.com](http://agileconsultingllc.com)  
removed\_email\_address@domain.invalid