我正在关注此Python Flask From Scratch，我现在正处于编辑和删除帖子的部分。我已经完全遵循了教程，甚至复制了解决方案代码，以替换我编写的代码以查看是否有错误，但我仍然收到错误消息
_mysql_exceptions.OperationalError：（1292，＆＃34;截断错误的DOUBLE值：＆＃39; 1}＆＃39;＆＃34;）
我已经确定此代码是问题，因为在添加edit_article部分之前程序正在查找。
# Edit Article
@app.route('/edit_article/<string:id>', methods=['GET', 'POST'])
@is_logged_in
def edit_article(id):
# Create cursor
cur = mysql.connection.cursor()
# Get article by id
result = cur.execute("SELECT * FROM articles WHERE id = %s", [id])
article = cur.fetchone()
cur.close()
# Get form
form = ArticleForm(request.form)
# Populate article form fields
form.title.data = article['title']
form.body.data = article['body']
if request.method == 'POST' and form.validate():
title = request.form['title']
body = request.form['body']
# Create Cursor
cur = mysql.connection.cursor()
app.logger.info(title)
# Execute
cur.execute ("UPDATE articles SET title=%s, body=%s WHERE id=%s",(title, body, id))
# Commit to DB
mysql.connection.commit()
#Close connection
cur.close()
flash('Article Updated', 'success')
return redirect(url_for('dashboard'))
return render_template('edit_article.html', form=form)
完整代码：
from flask import Flask, render_template, flash, redirect, url_for, session, logging, request
from flask_mysqldb import MySQL
from wtforms import Form, StringField, TextAreaField, PasswordField, validators
from passlib.hash import sha256_crypt
from functools import wraps
app = Flask(__name__)
# Config MySQL
app.config['MYSQL_HOST'] = 'localhost'
app.config['MYSQL_USER'] = 'root'
app.config['MYSQL_PASSWORD'] = '***************'
app.config['MYSQL_DB'] = 'myflaskapp'
app.config['MYSQL_CURSORCLASS'] = 'DictCursor'
# init MySQL
mysql = MySQL(app)
# Index
@app.route('/')
def index():
return render_template('home.html')
# About
@app.route('/about')
def about():
return render_template('about.html')
# Articles
@app.route('/articles')
def articles():
# Create cursor
cur = mysql.connection.cursor()
# Get articles
result = cur.execute("SELECT * FROM articles")
articles = cur.fetchall()
if result > 0:
return render_template('articles.html', articles=articles)
else:
msg = 'No Articles Found'
return render_template('articles.html', msg=msg)
# Close connection
cur.close()
# Single Article
@app.route('/article/<string:id>/')
def article(id):
# Create cursor
cur = mysql.connection.cursor()
# Get article
result = cur.execute("SELECT * FROM articles WHERE id = %s", [id])
article = cur.fetchone()
return render_template('article.html', article=article)
# Register Form Class
class RegisterForm(Form):
name = StringField('Name', [validators.Length(min=1, max=50)])
username = StringField('Username', [validators.Length(min=4, max=25)])
email = StringField('Email', [validators.Length(min=6, max=50)])
password = PasswordField('Password', [
validators.DataRequired(),
validators.EqualTo('confirm', message='Passwords do not match')
])
confirm = PasswordField('Confirm Password')
# Register
@app.route('/register', methods=['GET', 'POST'])
def register():
form = RegisterForm(request.form)
if request.method == 'POST' and form.validate():
name = form.name.data
email = form.email.data
username = form.username.data
password = sha256_crypt.encrypt(str(form.password.data))
# Create cursor
cur = mysql.connection.cursor()
# Execute query
cur.execute("INSERT INTO users(name, email, username, password) VALUES(%s, %s, %s, %s)", (name, email, username, password))
# Commit to DB
mysql.connection.commit()
cur.close()
flash('You are now registered and can log in', 'positive')
return redirect(url_for('login'))
return render_template('register.html', form=form)
# User Login
@app.route("/login", methods=['GET', 'POST'])
def login():
if request.method == 'POST':
# Get Form Fields
username = request.form['username']
password_candidate = request.form['password']
# Create cursor
cur = mysql.connection.cursor()
# Get User by username
result = cur.execute("SELECT * FROM users WHERE username = %s", [username])
if result > 0:
# Get stored hash
data = cur.fetchone()
password = data['password']
# Compare passwords
if sha256_crypt.verify(password_candidate, password):
# Passed
session['logged_in'] = True
session['username'] = username
flash('You are now logged in', 'success')
return redirect(url_for('dashboard'))
else:
error = 'Invalid login'
return render_template('login.html', error=error)
# Close connection
cur.close()
else:
error = 'Username not found'
return render_template('login.html', error=error)
return render_template('login.html')
# Check if user logged in / unauthorized
def is_logged_in(f):
@wraps(f)
def wrap(*args, **kwargs):
if 'logged_in' in session:
return f(*args, **kwargs)
else:
flash('Unauthorized, Please login', 'negative')
return redirect(url_for('login'))
return wrap
# Logout
@app.route('/logout')
@is_logged_in
def logout():
session.clear()
flash('You are now logged out', 'positive')
return redirect(url_for('login'))
# Dashboard
@app.route('/dashboard')
@is_logged_in
def dashboard():
# Create cursor
cur = mysql.connection.cursor()
# Get articles
result = cur.execute("SELECT * FROM articles")
articles = cur.fetchall()
if result > 0:
return render_template('dashboard.html', articles=articles)
else:
msg = 'No Articles Found'
return render_template('dashboard.html', msg=msg)
# Close connection
cur.close()
# Article Form Class
class ArticleForm(Form):
title = StringField('Title', [validators.Length(min=1, max=200)])
body = TextAreaField('Body', [validators.Length(min=30)])
# Add Article
@app.route('/add_article', methods=['GET', 'POST'])
@is_logged_in
def add_article():
form = ArticleForm(request.form)
if request.method == 'POST' and form.validate():
title = form.title.data
body = form.body.data
# Create Cursor
cur = mysql.connection.cursor()
# Execute
cur.execute("INSERT INTO articles(title, body, author) VALUES(%s, %s, %s)", (title, body, session['username']))
# Commit to DB
mysql.connection.commit()
# Close Connection
cur.close()
flash('Article Created', 'positive')
return redirect(url_for('dashboard'))
return render_template('add_article.html', form=form)
# Edit Article
@app.route('/edit_article/<string:id>', methods=['GET', 'POST'])
@is_logged_in
def edit_article(id):
# Create cursor
cur = mysql.connection.cursor()
# Get article by id
result = cur.execute("SELECT * FROM articles WHERE id = %s", [id])
article = cur.fetchone()
cur.close()
# Get form
form = ArticleForm(request.form)
# Populate article form fields
form.title.data = article['title']
form.body.data = article['body']
if request.method == 'POST' and form.validate():
title = request.form['title']
body = request.form['body']
# Create Cursor
cur = mysql.connection.cursor()
app.logger.info(title)
# Execute
cur.execute ("UPDATE articles SET title=%s, body=%s WHERE id=%s",(title, body, id))
# Commit to DB
mysql.connection.commit()
#Close connection
cur.close()
flash('Article Updated', 'success')
return redirect(url_for('dashboard'))
return render_template('edit_article.html', form=form)
if __name__ == '__main__':
app.secret_key = 'secret123'
app.run(debug=True)
答案 0 :(得分：0)
粗略地看一眼，看起来错误发生在这里：
cur.execute ("UPDATE articles SET title=%s, body=%s WHERE id=%s",(title, body, id))
问题1）id没有用标题和正文定义：
title = request.form['title']
body = request.form['body']
问题2）如果ID是数字，则需要格式化为“执行”＃39;带％d的字符串。
cur.execute ("UPDATE articles SET title=%s, body=%s WHERE id=%d",(title, body, id))