Tornadao—模板语法（控制语句）

• 控制语句

  ---

  可以在Tornado模板中使⽤Python条件和循环语句。控制语句以{\%和\%}包围，
  并以类似下⾯的形式被使⽤：
  {% if page is None %}
  或
  {% if len(entries) == 3 %}

  ---

  控制语句的⼤部分就像对应的Python语句⼀样⼯作，⽀持if、for、while，注意
  end:
  {% if ... %} ... {% elif ... %} ... {% else ... %} ... {% end %}
  {% for ... in ... %} ... {% end %}
  {% while ... %} ... {% end %}

  ---

  <ul class="house-list">
   {% if len(houses) > 0 %}
   {% for house in houses %}
   <li class="house-item">
   <a href=""><img src="/static/images/home01.jpg"></a>
   <div class="house-desc">
   <div class="landlord-pic"><img
  src="/static/images/landlord01.jpg"></div>
   <div class="house-price">￥<span>{{house["price"]}}
  </span>/晚</div>
   <div class="house-intro">
   <span class="house-title">{{house["title"]}}
  </span>
   <em>整套出租 - {{house["score"]}}
  分/{{house["comments"]}}点评 - {{house["position"]}}</em>
   </div>
   </div>
   </li>
   {% end %}
   {% else %}
   对不起，暂时没有房源。
   {% end %}
  </ul>

  ---

  class IndexHandler(RequestHandler):
   def get(self):
   houses = [
   {
   "price": 398,
   "title": "宽窄巷⼦+160平⼤空间+⽂化保护区双地铁",
   "score": 5,
   "comments": 6,
   "position": "北京市丰台区六⾥桥地铁"
   },
   {
   "price": 398,
   "title": "宽窄巷⼦+160平⼤空间+⽂化保护区双地铁",
   "score": 5,
   "comments": 6,
   "position": "北京市丰台区六⾥桥地铁"
   },
   {
   "price": 398,
   "title": "宽窄巷⼦+160平⼤空间+⽂化保护区双地铁",
   "score": 5,
   "comments": 6,
   "position": "北京市丰台区六⾥桥地铁"
   },
   {
   "price": 398,
   "title": "宽窄巷⼦+160平⼤空间+⽂化保护区双地铁",
   "score": 5,
   "comments": 6,
   "position": "北京市丰台区六⾥桥地铁"
   },
   {
   "price": 398,
   "title": "宽窄巷⼦+160平⼤空间+⽂化保护区双地铁",
   "score": 5,
   "comments": 6,
   "position": "北京市丰台区六⾥桥地铁"
   }]
   self.render("index.html", houses=houses)