3.4. 控制语句

3.4 控制语句

常用的几种控制语句：

模板中的if控制语句

@app.route('/user')
def user():
    user = 'dongGe'
    return render_template('user.html',user=user)


 <html>
 <head>
     {% if user %}
        <title> hello {{user}} title>
    {% else %}
         <title> welcome to flask title>        
    {% endif %}
 head>
 <body>
     <h1>hello worldh1>
 body>
 html>

模板中的for循环语句

 @app.route('/loop')
 def loop():
    fruit = ['apple','orange','pear','grape']
    return render_template('loop.html',fruit=fruit)

 <html>
 <head>
     {% if user %}
        <title> hello {{user}} title>
    {% else %}
         <title> welcome to flask title>        
    {% endif %}
 head>
 <body>
     <h1>hello worldh1>
    <ul>
        {% for index in fruit %}
            <li>{{ index }}li>
        {% endfor %}
    ul>
 body>
 html>