blocks|key|896046|text|users.each_with_index+do+%7Cu,+index%7C
++#+some+code
++if+index+==+users.size+-+1
++++#+code+for+the+last+user
++end
end|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|896047|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>users.each_with_index do |u, index|
 # some code
 if index == users.size - 1
 # code for the last user
 end
end
</code></pre>

blocks|key|896064|text|你试过each_with_index吗？|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|896065|users.each_with_index+do+%7Cu,+i%7C
++if+users.size-1+==+i
+++++#code+for+last+items
++end
end|code-block|syntax|javascript|896066|entityMap^0|3|F|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

Did you tried <code>each_with_index</code>? 

<pre><code>users.each_with_index do |u, i|
 if users.size-1 == i
 #code for last items
 end
end
</code></pre>

blocks|key|896073|text|h+=+{+:a+=>+:aa,+:b+=>+:bb+}
h.each_with_index+do+%7C(k,v),+i%7C
++puts+'+Put+last+element+logic+here'+if+i+==+h.size+-+1
end|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|896074|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>h = { :a =&gt; :aa, :b =&gt; :bb }
h.each_with_index do |(k,v), i|
 puts ' Put last element logic here' if i == h.size - 1
end
</code></pre>

blocks|key|896085|text|我认为最好的方法是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|896086|users.each+do+%7Cu%7C
++#code+for+everyone
++if+u.equal?(users.last)
++++#code+for+the+last+user
++end
end|code-block|syntax|javascript|896087|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

I think a best approach is:

<pre><code>users.each do |u|
 #code for everyone
 if u.equal?(users.last)
 #code for the last user
 end
end
</code></pre>

blocks|key|896154|text|对于ruby的某些版本，没有最后一种散列方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|896155|h+=+{+:a+=>+:aa,+:b+=>+:bb+}
last_key+=+h.keys.last
h.each+do+%7Ck,v%7C
++++puts+"Put+last+key+#{k}+and+last+value+#{v}"+if+last_key+==+k
end|code-block|syntax|javascript|896156|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

There are no last method for hash for some versions of ruby

<pre><code>h = { :a =&gt; :aa, :b =&gt; :bb }
last_key = h.keys.last
h.each do |k,v|
 puts "Put last key #{k} and last value #{v}" if last_key == k
end
</code></pre>

blocks|key|896193|text|另一个解决方案是从StopIteration中拯救出来：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|896194|user_list+=+users.each

begin
++while+true+do
++++user+=+user_list.next
++++user.do_something
++end
rescue+StopIteration
++user.do_something
end|code-block|syntax|javascript|896195|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Another solution is to rescue from StopIteration:

<pre><code>user_list = users.each

begin
 while true do
 user = user_list.next
 user.do_something
 end
rescue StopIteration
 user.do_something
end
</code></pre>

blocks|key|1111023|text|有时我发现将逻辑分成两部分更好，一部分用于所有用户，另一部分用于最后一个用户。所以我会这样做：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1111024|users[0...-1].each+do+%7Cuser%7C
++method_for_all_users+user
end

method_for_all_users+users.last
method_for_last_user+users.last|code-block|syntax|javascript|1111025|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Sometimes I find it better to separate the logic to two parts, one for all users and one for the last one. So I would do something like this:

<pre><code>users[0...-1].each do |user|
 method_for_all_users user
end

method_for_all_users users.last
method_for_last_user users.last
</code></pre>

blocks|key|1111072|text|您还可以将@meager的方法用于非此即彼的情况，在这种情况下，您将一些代码应用于除最后一个用户之外的所有用户，然后将一些独特的代码仅应用于最后一个用户。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1111073|users[0..-2].each+do+%7Cu%7C
++#code+for+everyone+except+the+last+one,+if+the+array+size+is+1+it+gets+never+executed
end

users.last.do_stuff()+#+code+for+last+user|code-block|syntax|javascript|1111074|这样你就不需要条件了！|1111075|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

You can use @meager's approach also for an either/or situation, where you're applying some code to all but the last user and then some unique code to only the last user.

<pre><code>users[0..-2].each do |u|
 #code for everyone except the last one, if the array size is 1 it gets never executed
end

users.last.do_stuff() # code for last user
</code></pre>

This way you don't need a conditional!

If i have a loop such as 

<pre><code>users.each do |u|
 #some code
end
</code></pre>

Where users is a hash of multiple users. What's the easiest conditional logic to see if you are on the last user in the users hash and only want to execute specific code for that last user so something like

<pre><code>users.each do |u|
 #code for everyone
 #conditional code for last user
 #code for the last user
 end
end
</code></pre>

Tell the end of a .each loop in ruby

如果我有一个循环，比如users.each do |u|  #some codeend其中users是多个用户的散列。如果您在用户散列中的最后一个用户上，并且只想为最后一个用户执行特定的代码，那么最简单的条件逻辑是什么users.each do |u|  #code for everyone  #conditional...

问用拼音表示.each循环的结束
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