@app.context_processor
def mycontext():
username = session.get('user')
if username:
return {'username':username}
else:
return {}
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>{% block title %}简书% endblock %}</title>
{% block head %}{% endblock %}
</head>
<body class="box">
<nav>
<a class="logo" href="http://www.jianshu.com/">
<img src="http://cdn2.jianshu.io/assets/web/logo-58fd04f6f0de908401aa561cda6a0688.png" alt="Logo"></a>
<a href="http://127.0.0.1:5000/base2">首页</a>
{% if username %}
<a href="#">{{ username }}</a>
<a href="{{ url_for('logout') }}">注销</a>
{% else %}
<a href="{{ url_for('login') }}">登陆</a>
<a href="{{ url_for('register') }}">注册</a>
{% endif %}
<input type="text"name="search">
<button type="submit">搜索</button>
</nav>
<hr>
{% block main %}{% endblock %}
</body>
</html>
@app.route('/logout/')
def logout():
session.clear()
return redirect(url_for('index'))
