Merge branch 'develop' of https://bdgit.educoder.net/Hjqreturn/pgfqe6ch8 into develop

app/views/subjects/_subject_item.html.erb

@@ -20,8 +20,8 @@
               <span class="mr10 fl squareIconSpan">
                 <i class="iconfont icon-shixun fl mr3" data-tip-down="章节"></i><%= subject.stages_count %></span>
           <% end %>
-          <% if subject.member_count > 0 %>
-              <span class="mr10 fl squareIconSpan"><i class="iconfont icon-chengyuan fl mr3" data-tip-down="学习人数"></i><%= subject.member_count %></span>
+          <% if subject.try(:member_count).to_i > 0 %>
+              <span class="mr10 fl squareIconSpan"><i class="iconfont icon-chengyuan fl mr3" data-tip-down="学习人数"></i><%= subject.try(:member_count) %></span>
           <% end %>
         </p>
       </div>