封装了一下取得logo的方法

app/controllers/welcome_controller.rb

@@ -39,8 +39,35 @@ class WelcomeController < ApplicationController
     @courseCount = Project.course_entities.count
     @teacherCount = User.teacher.count
     @studentCount = User.student.count
+    @logoLink = logolink(params[:school_id])
   end
   
+  
+  
+ def logolink(id)
+    logo_link = ""
+    if id.nil? and User.current.user_extensions.school.nil?
+      logo_link = '/images/transparent.png'
+    else
+      if id.to_i == 0
+        logo_link = '/images/transparent.png'
+      else
+        if id.nil?
+          if School.find(User.current.user_extensions.school.id).logo_link.nil?
+            logo_link = '/images/transparent.png'
+          else
+            logo_link = School.find(User.current.user_extensions.school.id).logo_link
+          end
+        else
+          logo_link = School.find(id).logo_link
+
+        end
+      end
+    end
+    return logo_link
+  end
+  
+  
   def contest
 
   end

app/views/welcome/course.html.erb

@@ -20,29 +20,8 @@
 	</div> 
 	<div class="main-content-bar">
 		<div style="float: left">
+		  	<%= image_tag(@logoLink, size:'75x75') %>
 		  	
-
-			<% if params[:school_id].nil? and User.current.user_extensions.school.nil? %>
-				<%= image_tag '/images/transparent.png', size: "75x75" %>
-			<% else%>
-				<% if params[:school_id] == "0" %>
-					<%= image_tag '/images/transparent.png', size: "75x75" %>
-				<% else %>
-					<% if params[:school_id].nil? %>
-						<% if School.find(User.current.user_extensions.school.id).logo_link.nil? %>
-							<%= image_tag '/images/transparent.png', size: "75x75" %>
-						<% else %>
-							<%#= image_tag('/images/school/default.png', size: "75x75") %>
-							<%= image_tag(School.find(User.current.user_extensions.school.id).logo_link, size: "75x75") %>
-						<% end %>
-						<br />
-					<% else %>
-						<%= image_tag(School.find(params[:school_id]).logo_link, size: "75x75") %>
-						<%#= image_tag('/images/school/default.png', size: "75x75") %>
-						<br />
-					<% end %>
-				<% end %>
-			<% end %>	
 		</div>		
 	<div class="welcome_left" >