12.6

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)

@app.route('/xiangqing/<question_id>')     
def xiangqing(question_id):
    quest=question.query.filter(question.id==question_id).first()
    return render_template('xiangqing.html',quse=quest)

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

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 }}

<li class="list-group-item" style="clear: both">
        <span class="glyphicon glyphicon-leaf" aria-hidden="true"></span>
        <a href="#">name:{{ foo.author.username }}</a>
        <br>
        <a href="{{ url_for('xiangqing',question_id=foo.id )}}">title:{{ foo.title }}</a><br> 
        <span class="badge">time:{{ foo.creat_time }}</span> 
        <p style="color: indianred">view:{{ foo.datail }}</p> </li> {% endfor %}

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'))
    creat_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'))