完成评论功能

1. 定义评论的视图函数
   @app.route('/comment/',methods=['POST'])
   def comment()：
   读取前端页面数据，保存到数据库中
2. 用<input type="hidden" 方法获取前端的"question_id" 
3. 显示评论次数
4. 要求评论前登录
5. 尝试实现详情页面下的评论列表显示

py

from flask import Flask, render_template, request, redirect, url_for, session
from flask_sqlalchemy import SQLAlchemy
from functools import wraps
from datetime import datetime
import config

app = Flask(__name__)
app.config.from_object(config)
db = SQLAlchemy(app)


class User(db.Model):
    __tablename__ = 'user'
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    Username = db.Column(db.String(20), nullable=False)
    Password = db.Column(db.String(20), nullable=False)
    Telphone = db.Column(db.String(20), nullable=True)


class Question(db.Model):
    __tablename__ = 'question'
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    author_id = db.Column(db.Integer,db.ForeignKey('user.id'))
    title = db.Column(db.String(100), nullable=False)
    detail = db.Column(db.Text, nullable=False)
    creat_time = db.Column(db.DateTime, default=datetime.now)
    author = db.relationship('User', backref=db.backref('question'))

class Comment(db.Model):
    __tablename__ = 'comment'
    id = db.Column(db.Integer, primary_key=True, autoincrement=True)
    author_id = db.Column(db.Integer,db.ForeignKey('user.id'))#外键
    question_id=db.Column(db.Integer,db.ForeignKey('question.id'))#外键
    detail = db.Column(db.Text, nullable=False)
    creat_time = db.Column(db.DateTime, default=datetime.now)
    question=db.relationship('Question',backref=db.backref('comments',order_by=creat_time.desc))
    author = db.relationship('User', backref=db.backref('comments'))
# db.create_all()


@app.route('/',methods=['GET','POST'])
def index():
    context = {
         'questions':Question.query.all()
    }
    return render_template('index.html',**context)

@app.route('/login/', methods=['GET', 'POST'])
def login():
    if request.method == 'GET':
        return render_template('login.html')
    else:
        usern = request.form.get('Username')
        passn = request.form.get('Password')
        user = User.query.filter(User.Username == usern).first()
        if user:
            if user.Password == passn:
                session['user'] = usern
                return redirect(url_for('index'))
            else:
                return '密码错误'
                # return window.alert("密码错误")
        else:
            # return window.alert("用户名不存在")
            return '用户名不存在'


@app.context_processor
def mycontext():
    usern = session.get('user')
    if usern:
        return {'Username': usern}
    else:
        return {}


def login_re(func):
    @wraps(func)
    def wrapper(*args, **kwargs):
        if session.get('user'):
            return func(*args, **kwargs)
        else:
            return redirect(url_for('login'))

    return wrapper


@app.route('/logout/')
def logout():
    session.clear()
    return redirect(url_for("index"))


@app.route('/register/', methods=['GET', 'POST'])
def register():
    if request.method == 'GET':
        return render_template('register.html')
    else:
        usern = request.form.get('Username')
        passn = request.form.get('Password')
        teln = request.form.get('Telphone')
        user = User.query.filter(User.Username == usern).first()
        if user:
            return '用户名已经存在'
        else:
            user1 = User(Username=usern, Password=passn, Telphone=teln)
            db.session.add(user1)
            db.session.commit()
            return redirect(url_for('login'))


@app.route('/question/', methods=['GET', 'POST'])
@login_re
def question():
    if request.method == 'GET':
        return render_template('question.html')
    else:
        an = User.query.filter(User.Username == session.get('user')).first().id
        tn= request.form.get('title')
        dn = request.form.get('detail')
        question1 = Question(author_id=an,title=tn, detail=dn)
        # question.author=User
        db.session.add(question1)  # 数据库，添加操作
        db.session.commit() #提交
    return redirect(url_for('index'))

@app.route('/detail/<question_id>')
def detail(question_id):
    quest=Question.query.filter(Question.id==question_id).first()
    return render_template('detail.html', ques=quest)
    # return redirect(url_for("detail.html"))


@app.route('/comment/', methods=['POST'])
@login_re
def comment():
        comment= request.form.get('commentdetail')
        ques_id=request.form.get('question_id')
        auth_id=User.query.filter(User.Username==session.get('user')).first().id
        comm=Comment(author_id=auth_id,question_id=ques_id,detail=comment)
        # question.author=User
        db.session.add(comm)  # 数据库，添加操作
        db.session.commit() #提交
        return redirect(url_for('detail', question_id=ques_id))


if __name__ == '__main__':
    app.run(debug=True)

 

html

{% extends 'base.html' %}
{% block title %}详情页{% endblock %}
{% block head %}
    {#    <script src="{{ url_for('static',filename='js/base.js') }}" type="text/javascript"></script>#}
    <link rel="stylesheet" type="text/css" href="{{ url_for('static',filename='css/detail.css') }}">
{% endblock %}

{% block main %}
    <div align="center">
        <div class="xianshi">
            <h3>{{ ques.title }}<br>
                <small>{{ ques.author.Username }}
                    <span class="badge">{{ ques.creat_time }}</span></small>
            </h3>
        </div>
        <p class="lead">{{ ques.detail }}</p>
        <hr>
        <form action="{{ url_for('comment') }}" method="post">
            <div class="ping">
                <div class="pinglun"><label for="comment">评论</label><br></div>
                <textarea id="comment" rows="8" name="commentdetail" PLACEHOLDER="写下你的评论"></textarea>
                <input name="question_id" type="hidden" value="{{ ques.id }}"/>
                <div class="but">
                    <button type="submit" class="fasong">发送评论</button>
                </div>
                <h4 align="left">评论:({{ ques.comments|length }})</h4>
            </div>
        </form>
        <div class="pl">
            <ul>
                {% for foo in ques.comments %}
                    <li>
                        <a href="#">{{ foo.author.Username }}</a>
                        <a class="creat_time" href="#">{{ foo.creat_time }}</a>
                        <a class="title" href="{{ url_for('detail',question_id=foo.id) }}">{{ foo.title }}</a>
                        <p class="abstract">{{ foo.detail }}</p>
                    </li>
                {% endfor %}</ul>
        </div>
    </div>
{% endblock %}