TutorialsPoint - Flask - SQLAlchemy无效

Question

我完成了教程点上的所有内容(只是复制和粘贴),但当我尝试添加学生条目时,即"添加学生",它给出了

错误请求浏览器(或代理)发送了此服务器无法理解的请求.

请告知本教程是否有任何问题.

它在def new()中的这一行失败了,在app.py中:

 student = students(request.form['name'], request.form['city'], request.form['addr'], request.form['pin'])

无论谁将其标记下来.请注意,这是一个充满拼写错误和错误缩进的教程.我只是一名学生.关闭它,我什么都不会学到.

参考:http://www.tutorialspoint.com/flask/flask_sqlalchemy.htm

from flask import Flask, request, flash, url_for, redirect, render_template
from flask_sqlalchemy import SQLAlchemy

app = Flask(__name__)
app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///students.sqlite3'
app.config['SECRET_KEY'] = "random string"

db = SQLAlchemy(app)

class Students(db.Model):
    id = db.Column('student_id', db.Integer, primary_key = True)
    name = db.Column(db.String(100))
    city = db.Column(db.String(50))
    addr = db.Column(db.String(200)) 
    pin = db.Column(db.String(10))

    def __init__(self, name, city, addr,pin):
        self.name = name
        self.city = city
        self.addr = addr
        self.pin = pin

    @app.route('/')
    def show_all():
        return render_template('show_all.html', Students = Students.query.all() )

    @app.route('/new', methods = ['GET', 'POST'])
    def new():
        if request.method == 'POST':
            if not request.form['name'] or not request.form['city'] or not request.form['addr']:
                flash('Please enter all the fields', 'error')
        else:
            print "1";
            student = Students(request.form['name'], request.form['city'], request.form['addr'], request.form['pin'])

            print "1";
            db.session.add(student)
            print "1";
            db.session.commit()
            print "1";
            flash('Record was successfully added')
            print "=======>>>>>>>>>";
            return redirect(url_for('show_all'))
        return render_template('new.html')

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

Answer 1

该教程在学生班中有缩进问题.构造函数代码应缩进一级,以便它成为学生类的方法.

更正代码:(注意下面代码中的"def init(self,name,city,addr,pin):" 的缩进)

class students(db.Model):
   id = db.Column('student_id', db.Integer, primary_key = True)
   name = db.Column(db.String(100))
   city = db.Column(db.String(50))
   addr = db.Column(db.String(200)) 
   pin = db.Column(db.String(10))

   def __init__(self, name, city, addr,pin):
      self.name = name
      self.city = city
      self.addr = addr
      self.pin = pin

原因是,如果那个缩进不存在,python将不会将此函数视为学生类的构造函数.因此找不到具有匹配数量的参数的构造函数,从而导致错误.