course manager can not apply to join that course

app/services/courses_service.rb

@@ -303,6 +303,7 @@ class CoursesService
   #@state == 7 您已经发送过申请了，请耐心等待
   #@state == 8 您已经是该课程的教师了
   #@state == 9 您已经是该课程的教辅了
+  #@state == 10 您已经是该课程的管理员了
   #@state 其他 未知错误，请稍后再试
   def join_course params,current_user
     course = Course.find_by_id params[:object_id]
@@ -325,6 +326,8 @@ class CoursesService
             #如果加入的角色教辅并且当前为教辅
             elsif params[:role] == "7" && roleName == "TeachingAsistant"
               @state = 9
+            elsif roleName == "Manager"
+              @state = 10
             #如果加入角色为教师或者教辅，并且当前是学生，或者是要成为教辅，当前不是教辅，或者要成为教师，当前不是教师。那么要发送请求
             elsif (params[:role] != "10" && roleName == "Student") || (params[:role] == "7" && roleName != "TeachingAsistant" ) || (params[:role] == "9" && roleName != "Teacher" )
               #如果已经发送过消息了，那么就要给个提示

app/views/courses/join.js.erb

@@ -32,6 +32,10 @@ window.location.href= "http://"+"<%= Setting.host_name%>"+"/courses/" + "<%= @co
 alert("您已经是该课程的教辅了");
 hidden_join_course_form();
 window.location.href= "http://"+"<%= Setting.host_name%>"+"/courses/" + "<%= @course.id%>"
+<% elsif @state == 10%>
+alert("您已经是该课程的管理员了");
+hidden_join_course_form();
+window.location.href= "http://"+"<%= Setting.host_name%>"+"/courses/" + "<%= @course.id%>"
 <% else %>
 alert("未知错误，请稍后再试");
 <% end %>