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POHow can i simplify conditions when i have much params in my search?
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  1. POHow can i simplify conditions when i have much params in my search?
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    copied!<p>For example</p> <p>I have 5 params in my search view:</p> <pre><code> params[:a] params[:b] params[:c] params[:d] params[:e] </code></pre> <p>And I want to search in my controller when:</p> <pre><code> params[:a].present? and params[:b].nil? params[:a].present? and params[:c].nil? params[:a].present? and params[:e].nil? params[:b].present? and params[:c].nil? params[:b].present? and params[:d].nil? ............ params[:a].nil? and params[:b].nil? ............. </code></pre> <p>Here is what I tried:</p> <pre><code> controller: if params[:a].nil? @query else if params[b].nil? @another_query else ...........#and it will continue with lots of conditions according with params end end </code></pre> <p>Well there are lots of conditions that I can try</p> <p>Here is using a real example I got this error "undefined method `paginate' for nil:NilClass"</p> <pre><code> #table policies id num_policy type_id doc name 1 2323 1 181844 Charles 2 2121 2 151511 Aguardientico 3 3423 2 434344 Benjamin #controller if params[:num_policy].present? @search= Policy.find(:all,:conditions=&gt;['num_policy LIKE ?',params[:num_policy] ]) end if params[:type_id].present? @search= Policy.find(:all,:conditions=&gt;['type_id LIKE ?',params[:type_id] ]) end if params[:doc].present? @search= Policy.find(:all,:conditions=&gt;['doc LIKE ?',params[:doc] ]) end if params[:name].present? @search= Policy.find(:all,:conditions=&gt;['name LIKE ?',params[:name] ]) end if params[:doc].present? and params[:type_id].present? @search= Policy.find(:all,:conditions=&gt;['doc LIKE ? and type_id LIKE ?',params[:doc],params[:type_id] ]) end @policies= @search.paginate( :page =&gt; params[:page], :per_page =&gt;2) #view &lt;% form_tag :controller=&gt;"policy",:action=&gt;"search" do %&gt; &lt;%= text_field_tag "num_policy",params[:num_policy] %&gt; &lt;%= text_field_tag "doc",params[:doc] % &lt;%= text_field_tag "name",params[:name] % &lt;%= text_field_tag "type_id",params[:type_id] % &lt;% end %&gt; &lt;% @policies.each do |p| %&gt; &lt;%= p.num_policy %&gt; &lt;%= p.type_id %&gt; &lt;%= p.doc %&gt; &lt;%= p.name %&gt; &lt;% end %&gt; </code></pre> <p>But if remove paginate I got this error "You have a nil object when you didn't expect it! You might have expected an instance of Array. The error occurred while evaluating nil.each"</p> <pre><code> #controller @policies= @search #says that my line &lt;% @policies.each do |p| %&gt; is nil </code></pre> <p>Is there any way to control them?</p> <p>Please i just want opinions maybe someone happened it too..</p> <p>Thanks.</p>
 

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