完成个人中心—导航标签

1. 个人中心—视图函数带标签页面参数tag
   @app.route('/usercenter/<user_id>/<tag>')
   def usercenter(user_id, tag):
      if tag == ‘1':
          return render_template('usercenter1.html', **context)
   
   
2. 个人中心—导航标签链接增加tag参数
   <li role=“presentation”><a href=“{{ url_for(‘usercenter’,user_id = user.id,tag = ‘1’) }}">全部问答</a></li>
   
   
3. 个人中心—有链接到个人中心页面的url增加tag参数
    <a href="{{ url_for('usercenter',user_id = session.get('userid'), tag=1) }}">{{ session.get('user') }}</a>

   @app.route('/usercenter/<user_id>/<tag>')
   @loginFirst
   def usercenter(user_id,tag):
       user=User.query.filter(User.id==user_id).first()
       context={
          'user':user
       }
       if tag=='1':
           return render_template('usercenter1.html', **context)
       if tag=='2':
           return render_template('usercenter2.html', **context)
       if tag == '3':
           return render_template('usercenter3.html',**context)

   {% extends "base.html" %}
   {% block title %}个人中心{% endblock %}
   {% block head %}
       <style>
           .nav nav-tabs li{
               list-style: none;
               float: left;
               margin: 25px;
           }
   
       </style>
   {% endblock %}
   
   {% block main %}
       <h3><span class="glyphicon glyphicon-user" aria-hidden="true"></span>{{ user.username }}</h3>
       <ul class="nav nav-tabs">
       <li role="presentation"><a href="{{ url_for('usercenter',user_id=user.id,tag=1) }}">全部问答</a></li>
       <li role="presentation"><a href="{{ url_for('usercenter',user_id=user.id,tag=2) }}">全部评论</a></li>
       <li role="presentation"><a href="{{ url_for('usercenter',user_id=user.id,tag=3) }}">个人信息</a></li>
       </ul>
   
       {% block user %}{% endblock %}
   
   {% endblock %}

   <a href="{{ url_for('usercenter',user_id=user.id,tag=1) }}">{{user.username }}</a>

   <a href="{{ url_for('usercenter',user_id=foo.author_id,tag=1) }}">{{ foo.author.username }}评论:({{ foo.comments|length }})</a><br>
   
   <a href="{{ url_for('usercenter',user_id=foo.author.id,tag=1) }}">{{ foo.author.username }}</a>