socialforge/app/views/welcome/_search_course.html.erb

<%
	select_option = []
	(select_option << [l('welcome.search.select.project'), 'projects']) if project_type == Project::ProjectType_project
	(select_option << [l('welcome.search.select.course'), 'courses']) if project_type == Project::ProjectType_course
	select_option << [l('welcome.search.select.user'), 'users']
	#select_option << ['教师', 'users_teacher'],
	#select_option << ['学生', 'users_student']
%>
<style type="text/css">
form #q, form #search_type{
	-webkit-box-sizing: border-box;
	-moz-box-sizing: border-box;
	box-sizing: border-box;
	display: inline-block;
	margin: 0px;
	padding: 5px;
	height: 33px;
}
form #q{
	font-size: 13px;
	border-top-left-radius: 5px;
	border-bottom-left-radius: 5px;
	border-right: none;

}
form #search_type{
	font-size: 13px;
	color: #363739;
	border-top-right-radius: 5px;
	border-bottom-right-radius: 5px;
	border-bottom-left-radius: 0px;
	border-top-left-radius: 0px;
	border-left: 1px outset #83A9A9;
	margin-left: -4px;
	-webkit-appearance: none;
	-moz-appearance: none;
	text-indent: 0.01px;
	text-overflow: '';
}
.search_widget{
	display:inline-block;
	border-radius: 5px;
}
.search_widget:hover{
	box-shadow: 0px 0px 3px #56B4EF;
}
<%#完了把上面东西放到 .css 里%>
</style>
<%= form_tag({controller: :welcome, action: :search }, method: :get) do %>
<div class="project-search" style="float: right">
	<div class='search_widget'>
		<%= text_field_tag :q, nil, :placeholder => l('welcome.search.information'), :size => 27, style: "float:left"  %>
		<%= select_tag(:search_type, options_for_select(select_option), :style => "float:right" ) %>
	</div>
		<%#= hidden_field_tag 'project_type', project_type %>
		<%= submit_tag l(:label_search), :class => "enterprise", :name => nil, :style => "float:right" %>
		</div>	
<% end %>