测开之路一百三十六：错误消息闪回提示

错误消息提示：flask.flash

视图

app.secret_key = 'qoihf2397r21380r2/./ad'  # 加密的安全码，越复杂越好，flask后台自动进行加密


@app.route('/login/', methods=['GET', 'POST'])
def login():
    """ 登录 """
    if request.method == 'POST':
        username = request.form.get('username')
        password = request.form.get('password')
        sql = 'select count(*) as [Count] from UserInfo where username = ? and password = ?'
        result = query_sql(sql, (username, password), True)
        if int(result.get('Count')) > 0:
            return redirect(url_for('list'))
        flash('用户名或密码错误')
    return render_template('login.html')

login.html

{% extends 'base.html' %}

{% block main_content %}

<!--登录界面-->
<div class="row">
    <div class="col-md-6 col-md-offset-3">
        <div class="panel panel-default">
            <div class="panel-heading">
                <h4>登录</h4>
            </div>
            <div class="panel-body">
                <form action="#" class="form-horizontal" method="post">
                    <div class="col-md-10 col-md-offset-1">
                        <!--错误消息闪现-->
                        {% with messages = get_flashed_messages() %}<!-- 获取flash返回的消息，语法由jinja2提供 -->
                            {% if messages %}
                                {% for msg in messages %}
                                    <div class="alert alert-warning">
                                        <a href="#" class="close" data-dismiss="alert">&times;</a>
                                        {{ msg }}
                                    </div>
                                {% endfor %}
                            {% endif %}
                        {% endwith %}
                        <div class="form-group">
                            <label for="username" class="col-md-3">用户名：</label>
                            <div class="col-md-7">
                                <input type="text" class="form-control" name="username" id="username">
                            </div>
                        </div>
                        <div class="form-group">
                            <label for="password" class="col-md-3">密码：</label>
                            <div class="col-md-7">
                                <input type="text" class="form-control" name="password" id="password">
                            </div>
                        </div>
                        <div class="form-group">
                            <div class="col-md-10 col-md-offset-3">
                                <input type="submit" class="btn btn-primary" value="登录">
                            </div>
                        </div>
                    </div>

                </form>
            </div>
            <div class="footer">
                &copy;版权所有
            </div>
        </div>
    </div>
</div>


{% endblock %}

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