从首页问答标题到问答详情页

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) }}
   
   
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 }}

4. 建立评论的对象关系映射：

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

5.  尝试实现发布评论。

@app.route('/detail?<wenda_id>')
def detail(wenda_id):
    wen = Wenda.query.filter(Wenda.id == wenda_id).first()
    return render_template('detail.html',wend=wen)

<a href="{{ url_for('detail',wenda_id = foo.id) }}">{{ foo.title }}</a>

{% for foo in questions %}
    <li class="list-group-item">
            <span class="glyphicon glyphicon-leaf" aria-hidden="true"></span>
            <a href="{{ url_for('detail',wenda_id = foo.id) }}">{{ foo.title }}</a>
    <p style="">{{ foo.detail }}</p>
    <span class="glyphicon glyphicon-user" aria-hidden="true"></span>
            <a href="">{{ foo.author.username }}</a>
    <span class="badge">{{ foo.creat_time }}</span>

    </li>
    {% endfor %}

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('wenda.id'))
    creat_time = db.Column(db.DateTime,default=datetime.now)
    detail = db.Column(db.Text,nullable=False)
    question = db.relationship('Wenda',backref = db.backref('comments'))
    author = db.relationship('User',backref = db.backref('co