Ruby-on-rails 如何在 Rails 视图中遍历数组？
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How can I iterate through an array in rails view?
提问by Carlos Morales
I did a query in MySql but is working in Rails and mysql2 gem.
我在 MySql 中做了一个查询，但在 Rails 和 mysql2 gem 中工作。
Here is the information:
以下是信息：
http://sqlfiddle.com/#!2/9adb8/6
The query is working fine without problems and showing this result:
查询工作正常，没有问题并显示以下结果：
UNIT V1 A1 N1 V2 A2 N2 V3 A3 N3 V4 A4 N4 V5 A5 N5
LIFE 2 0 0 1 2 0 0 0 0 0 0 0 0 0 0
ROB 0 1 0 0 1 2 0 0 0 0 0 0 0 0 0
-Installed mysql2 gem for rails 2.3.8
-为 rails 2.3.8 安装了 mysql2 gem
gem install mysql2 -v0.2.6
-Created the controller:
- 创建控制器：
class PolicyController < ApplicationController
def index
@result = ActiveRecord::Base.connection.execute("select distinct @sql := concat('SELECT pb.name as unit,',group_concat(concat('SUM(CASE WHEN p.state =0 AND ce.id=',id,' THEN 1 ELSE 0 END ) AS v',id,',SUM(CASE WHEN p.state =1 AND ce.id=',id,' THEN 1 ELSE 0 END ) AS a',id,',SUM(CASE WHEN p.state =2 AND ce.id=',id,' THEN 1 ELSE 0 END ) AS n',id)),' FROM cia_ensures ce LEFT JOIN policies p on ce.id = p.cia_ensure_id INNER JOIN policy_business_units pb ON pb.id = p.policy_business_unit_id INNER JOIN comercial_areas ca ON ca.id = pb.comercial_area_id AND ca.id=1 Group by p.policy_business_unit_id') from cia_ensures where id in(1,2,3,4,5);")
@result2 = ActiveRecord::Base.connection.execute("prepare stmt from @sql;")
@result3 = ActiveRecord::Base.connection.execute("execute stmt;")
end
end
Here is the log:
这是日志：
SQL (0.9ms) select distinct @sql := concat('SELECT pb.name as unit,',group_concat(concat('SUM(CASE WHEN p.state =0 AND ce.id=',id,' THEN 1 ELSE 0 END ) AS v',id,',SUM(CASE WHEN p.state =1 AND ce.id=',id,' THEN 1 ELSE 0 END ) AS a',id,',SUM(CASE WHEN p.state =2 AND ce.id=',id,' THEN 1 ELSE 0 END ) AS n',id)),' FROM cia_ensures ce LEFT JOIN policies p on ce.id = p.cia_ensure_id INNER JOIN policy_business_units pb ON pb.id = p.policy_business_unit_id INNER JOIN comercial_areas ca ON ca.id = pb.comercial_area_id AND ca.id=1 Group by p.policy_business_unit_id') from cia_ensures where id in(1,2,3,4,5);
SQL (0.9ms) prepare stmt from @sql;
SQL (0.2ms) execute stmt;
Here is the view (is working fine and without problems but seems to be too long write several times the same code)
这是视图（工作正常且没有问题，但编写相同代码的时间似乎太长了）
<table>
<% @result3.each do |policy| %>
<tr>
<td><%= policy[0] %></td>
<td><%= policy[1] %></td>
<td><%= policy[2] %></td>
<td><%= policy[3] %></td>
<td><%= policy[4] %></td>
<td><%= policy[5] %></td>
...
</tr>
<%end%>
</table>
I tried to use inspect but it shows all the information in one td and not on each td:
我尝试使用检查，但它显示了一个 td 中的所有信息，而不是每个 td：
<% @result3.each do |policy| %>
<tr>
<td align="center"><%= policy.inspect %></td>
</tr>
<%end%>
How can I do to show all this without writing lots of lines?
我怎样才能在不写很多行的情况下展示这一切？
Is it possible to make this in one line? without writing <%= policy[#NUMBER] %>
是否可以在一行中完成此操作？不写 <%= policy[#NUMBER] %>
Please somebody can help me with this?
请问有人可以帮我吗？
I will really appreciate it.
我会很感激的。
回答by Igor Pantovi?
Hmmm, might have missunderstood your question since it looks really simple, are you trying to shorten this?
嗯，可能误解了你的问题，因为它看起来很简单，你想缩短这个吗？
Change:
改变：
<td><%= policy[0] %></td>
<td><%= policy[1] %></td>
<td><%= policy[2] %></td>
<td><%= policy[3] %></td>
<td><%= policy[4] %></td>
<td><%= policy[5] %></td>
To:
到：
<% policy.each do |p| %>
<td><%= p %></td>
<% end %>
回答by Rajdeep Singh
Do this
做这个
<% @result3.each do |policy| %>
<tr>
<% policy.each { |p| raw "<td>#{p}</td>" } %>
</tr>
<%end%>
回答by toniedzwiedz
Just iterate over each collection in each policyobject.
只需迭代每个policy对象中的每个集合。
<table>
<% @result3.each do |policy| %>
<tr>
<%policy.each do |item| %>
<td><%= item %></td>
<%end%>
</tr>
<%end%>
</table>
