12.6

1. 主PY文件写视图函数，带id参数。 

   @app.route('/detail/<question_id>')
   def detail(question_id):
       quest = 
       return render_template('detail.html', ques = quest)

2. 首页标题的标签做带参数的链接。
         {{ url_for('detail',question_id = foo.id) }}
   

   {% block main %}
       <!--<img src="{{ url_for }}">-->
       <ul class="list-group">
       {% for foo in post %}
          <li class="list-group" >
              <span class="badge" aria-hidden="true"></span>
              <a href="#">{{ foo.author.username }}</a>
              <br>
              <a href="{{url_for('detail',post_id=foo.id)}}">{{foo.title}}</a>
              <span class="badge">{{ foo.creat_time }}</span>
              <p style="">{{ foo.detail }}</p>
   
          </li>
       {% endfor %}
       </ul>

    

3. 在详情页将数据的显示在恰当的位置。 

   {{ ques.title}}
   {{ ques.id  }}{{  ques.creat_time }}

   {{ ques.author.username }} 
   {{ ques.detail }}

   1. {% extends 'base.html' %}
      {% block title %}
          问答详情
      {% endblock %}
      {% block main %}
          <div class="box">
              <h1 href="#" >{{ ques.title }}</h1><small> {{ ques.author.username }}
      <span class="badge" style="margin-left: 75%">{{ ques.create_time }}</span></small>
              <hr>
              <p>{{ ques.detail }}</p>
              <hr>
              <form>
                  <div><textarea class="form-control" id="comment" rows="3" style="margin-left: 1%" name="comment"
       placeholder="write your comment"></textarea><br></div>
                  <button type="submit" >发送</button>
              </form>
            <h2>评论:</h2>
               <ul class="list-group">
                      <li class="list-group-item">
                          <img style="width: 50px" src="{{ url_for('static',filename='css/zhaopian.jpg') }}" alt="64">
                          <a href="#"></a><br>
                          <p style="align-content: center"></p>
                          <span class="badge" style="margin-left: 60%"></span>
                          <p style="margin-left: 25%"></p><br>
                      </li>
              </ul>
      
          </div>
      {% endblock %}

       

      4.建立评论的对象关系映射：

      class Comment(db.Model):
          __tablename__='comment'

      class Comment(db.Model):
           __tablename__ = 'comment'
           id = db.Column(db.Integer, primary_key=True, autoincrement=True)
           author_id = db.Column(db.Integer, db.ForeignKey('user.id'))
           question_id = db.Column(db.Integer, db.ForeignKey('question.id'))
           create_time = db.Column(db.DateTime, default=datetime.now)
           detail = db.Column(db.Text, nullable=False)
           question = db.relationship('Question',backref=db.backref('comments'))
           author = db.relationship('User',backref=db.backref('comments')