Alphabetical lists with ruby on rails
I am building a list that will be sorted by the alphabet a开发者_如何学JAVAnd am looking for a solution to grab the database result and sort it alphabetically.
Any help is greatly appreciated!
Building on thenduks above, I like:
Company.rb
def initial
return '?' if name.blank?
# name.[0].upcase (updated to get the first character )
name.slice(1).chr.upcase
end
view
<% # Company.all.group_by(&initial) do |initial, companies| (updated) %>
<% Company.all.group_by(&:initial).each do |initial, companies| %>
<%= content_tag(:h2, initial)%>
<% companies.each do |company|%>
<%= link_to(company.name, company%>
<% end %>
<% end %>
Hmm, if you have a list that isn't too massive you might just do it naively like:
(This assumes you have a model Company
which has a name
attribute)
@grouped = {}
Company.all.each do |company|
letter = company.name.slice(0,1).upcase
@grouped[letter] ||= []
@grouped[letter] << company
end
And now you can, in your view, do something such as:
<ul>
<% @grouped.keys.sort.each do |letter| -%>
<li>
<h2><%= letter %></h2>
<ul>
<% @grouped[letter].each do |company| -%>
<li><%= company.name %></li>
<% end -%>
</ul>
</li>
<% end -%>
</ul>
Update: If you want to extend the logic on what the 'letter' is, you would probably move the logic into the model, eg:
class Company
# ... code
def initial
# find a number at the start of the string if it exists
m = self.name.match(/^\d+/)
return m[0] if m
# or return the first letter upcased otherwise
return self.name.slice( 0, 1 ).upcase
end
end
Try this:
g = Company.all.group_by{|c|c.name.upcase[0..0]}
('A'..'Z').each do |letter|
companies = g[letter] || []
# process the name and the letter
end
This will work even in scenarios when you do not have items for few letters.
Note: You might want to handle the numbers and non English letters differently by modifying the group_by logic. You also have to change the letter name iteration list accordingly.
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