Flask 6 模板2
NOTE
Jinja2提供了多种控制程序,可以用来改变模板的渲染流程。
1.在模板中使用条件控制语句:
templates/condition.html:
{% if user %}
Hello, {{ user }}!
{% else %}
Hello, Stranger!
{% endif %}
hello.py:
#!/usr/bin/env python
from flask import Flask, render_template
app = Flask(__name__)
@app.route('/')
def index():
return render_template('condition.html')
@app.route('/user/<name>')
def user(name):
return render_template('condition.html', user=name)
if __name__ == '__main__':
app.run(debug=True)
localhost:5000 :
Hello, wasdns!
2.在模板中渲染一组元素:
<ul>
{% for comment in comments %}
<li>{{ comment }}</li>
{% endfor %}
</ul>
3.宏,类似函数:
{% macro render_comment(comment) %}
<li>{{ comment }}</li>
{% endmacro %}
<ul>
{% for comment in comments %}
{{ render_comment(comment) }}
{% endfor %}
</ul>
也可以将宏单独放在一个文件中,然后导入:
macros.html:
{% macro render_comment(comment) %}
<li>{{ comment }}</li>
{% endmacro %}
demo.html:
{% import 'macros.html' as macros %}
<ul>
{% for comment in comments %}
{{ render_comment(comment) }}
{% endfor %}
</ul>
4.继承:block标签定义的元素可以在衍生模板中进行修改。
base.html:
<html>
<head>
{% block head %}
<title>{% block title %}{% endblock %} - My Application</title>
{% block end %}
</head>
<body>
{% block body %}
{% endblock %}
</body>
</html>
extend.html:
{% extends "base.html "%}
{% block title %}Index{% endblock %}
{% block head %}
{{ super() }}
<style>
</style>
{% endblock %}
{% block body %}
<h1>Hello World!</h1>
{% endblock %}
super() => 获取基模板中原有内容。
2017/2/19
To improve is to change, to be perfect is to change often.