Python终端登录表单：用户注册数据无法正确存入JSON的Entries数组问题求助

Hey there! Let's get that user registration data saving correctly into your Entries array instead of as a top-level entry. The core issue is how you're adding the new user data to your JSON structure—here's the breakdown and fix:

What's Going Wrong #

Your write_json function uses file_data.update(new_data) which adds the new user's fields (User name, Password, ID) as top-level keys in your JSON file, right alongside the Entries array. That's why you're seeing the new user data outside the array instead of inside it.

The Fix #

We need to append the new user object directly to the Entries array instead of updating the root dictionary. Here's the revised code with key improvements:

import json

def write_json(new_data, filename='entries.json'):
    with open(filename,'r+') as file:
        file_data = json.load(file)
        # Append the new user to the Entries array instead of updating the root
        file_data['Entries'].append(new_data)
        file.seek(0)
        json.dump(file_data, file, indent = 4)
        # Truncate leftover content from the original file
        file.truncate()

print('Welcome to our company!')
print('Please enter your username here to login.')
name = input('Enter name: ')

# Load entries once, using a with block to auto-close the file
with open('entries.json', 'r') as f:
    content = json.load(f)
entries = content['Entries']

user_found = False
for e in entries:
    if name == e['User name']:
        user_found = True
        print('Please enter your password.')
        password = input('Enter password: ')
        if password == e['Password']:
            print(f'Welcome, {name}! You are now logged in!')
        else:
            print('Wrong password.')
        break

if not user_found:
    print('Your name is not in the file.')
    print('You need to register.')
    new_name = input('Please enter your name: ')
    new_password = input('Please enter your password: ')
    # Keep ID as an integer (matches existing data format)
    new_id = len(entries) + 1
    new_user = {
        "User name": new_name,
        "Password": new_password,
        "ID": new_id
    }
    write_json(new_user)
    print(f"Successfully registered: {new_user}")
    print('Your details have been added to the file.')

Key Improvements Made #

• Fixed JSON Saving: Replaced file_data.update(new_data) with file_data['Entries'].append(new_data) to add the new user to the correct array.
• Added File Truncation: file.truncate() ensures any leftover content from the original (longer) file is removed after writing the new data.
• Cleaned Up Login Logic: Removed the unnecessary outer for c in content loop (since content is a single dictionary with one key: Entries) and used a clear user_found flag to track if the user exists.
• Consistent Data Types: Kept the ID as an integer (matching your existing JSON data, instead of converting it to a string).

Result #

After running this revised code, your entries.json will have the new user correctly nested inside the Entries array, just like your expected output:

{
    "Entries": [
        {
            "User name": "Jerry",
            "Password": "56_jerry_56",
            "ID": 1
        },
        {
            "User name": "Willy_Wonka",
            "Password": "1111",
            "ID": 2
        },
        {
            "User name": "Anita",
            "Password": "438200219",
            "ID": 3
        },
        {
            "User name": "John",
            "Password": "john1",
            "ID": 4
        },
        {
            "User name": "arya",
            "Password": "arya1",
            "ID": 5
        }
    ]
}

内容的提问来源于stack exchange，提问作者Arya