Question

试图用flask和sqlite3创建一个简单的Web表单，我遇到了以下问题：

我运行了烧瓶，输入了一些测试名称和电子邮件，并在索引页面上看到了它们，但是当我去检查数据库中的最新行时，没有显示新数据。反过来，目录中出现了一个新的讲课.db-新闻文件。

我不知道是什么导致了这种行为，因此希望这里的人可以让我对我做错的事情有所了解。这是 application.py ：

from flask import Flask, render_template, request, redirect
import sqlite3

app = Flask(__name__)

# Connect with the lecture registrants database.
# Database structure - 'id' INTEGER | 'name' VARCHAR(255) | 'email' VARCHAR(255) 
connection = sqlite3.connect("lecture.db")
# Setting row_factory property of
# connection object to sqlite3.Row(sqlite3.Row is an implementation of
# row_factory).
connection.row_factory = sqlite3.Row
# cursor
db = connection.cursor()

# Display all the people who registered on the route page.
@app.route("/")
def index():
    sql_command = "SELECT * FROM registrants;"
    db.execute(sql_command)

    rows = db.fetchall()
    # Returns a list of dictionaries, each item in list(each dictionary)
    # represents a row of the table.

    return render_template("index.html", rows=rows)

@app.route("/register", methods=["GET", "POST"])
def register():
    if request.method == "GET":
        return render_template("register.html")
    else:
        # Update the database with the new name and email.
        name = request.form.get("name")
        email = request.form.get("email")

        sql_command = "INSERT INTO registrants (name, email) VALUES (?, ?);"
        db.execute(sql_command, [name, email])
        return redirect("/")

以下是用于显示数据的 index.html ：

<!DOCTYPE html>

<html lang="en">
    <head>
        <title>Registrants</title>
    </head>
    <body>
        <h1>List of all registrants</h1>
        <ul>
            {% for row in rows %}
                <li>{{ row["name"] }} ({{ row["email"] }})</li>
            {% endfor %}
        </ul>
        <a href="/register">Register here.</a>
    </body>
</html>

和 register.html 文件，格式为：

<!DOCTYPE html>

<html lang="en">
    <head>
        <title>Register</title>
    </head>
    <body>
        <h1>Register for the lecture</h1>
        <form action="/register" method="post">
            <input type="text" name="name" placeholder="Name">
            <input type="text" name="email" placeholder="Email address">
            <input type="submit">
        </form>

    </body>
</html>

http状态似乎正常：

  "GET / HTTP/1.0" 200 -
  "GET /register HTTP/1.0" 200 -
  "POST /register HTTP/1.0" 302 -
  "GET / HTTP/1.0" 200 -
  "GET / HTTP/1.0" 200

谢谢您的关注！欢迎任何评论。

Answer 1

您在以下时间忘记了commit()：

sql_command = "INSERT INTO registrants (name, email) VALUES (?, ?);"
db.execute(sql_command, [name, email])

https://docs.python.org/3.8/library/sqlite3.html

表单不会永久保存数据

1 个答案: