New Python Program: Basic File Manipulation

按照 issue 中的描述创建 file_manipulation.py，首先检查所需的菜单操作和 database.txt 工作流程。使用 Python 3 运行程序，并手动测试查看、添加、更新、删除、无效输入、文件缺失和文件错误等情况。每个操作都能正常运行，并且每次操作后都会保存更新的数据，即表示完成。

Hello Python enthusiasts! Let's expand our repository with a Python program that demonstrates basic file manipulation operations. This beginner-friendly task involves reading from and writing to text files, allowing users to create, read, update, and delete entries in a simple database file. This task will showcase file handling, loops, and conditional statements in Python.

Tasks:

• Create a Python program that reads data from a text file (database.txt) if it exists.
• Allow users to view existing entries, add new entries, update existing entries, and delete entries.
• Implement user-friendly menus and prompts for each operation.
• Ensure the program handles errors gracefully, such as invalid file access or incorrect user inputs.
• Save the updated data back to the text file after each operation.

Guidelines:

• Use Python 3.x for the program.
• Utilize file handling functions (open, read, write, close) to manipulate the database file.
• Include comments in your code to explain the logic and functionality.
• Test the program thoroughly, including edge cases and error scenarios.

Example:

Welcome to the Basic File Manipulation Program!

1. View Entries
2. Add Entry
3. Update Entry
4. Delete Entry
5. Exit

Select an option: 2
Enter name: John Doe
Enter age: 30
Entry added successfully!

1. View Entries
2. Add Entry
3. Update Entry
4. Delete Entry
5. Exit

Select an option: 1
Entries:
1. Name: John Doe, Age: 30

...

How to Contribute:

1. Fork this repository.
2. Create a new Python file for the Basic File Manipulation Program: file_manipulation.py.
3. Write the Python program following the specified tasks and guidelines.
4. Test the program thoroughly to ensure it functions correctly.
5. Commit your changes: git commit -m "Add Basic File Manipulation Program"
6. Push to your branch: git push origin add-file-manipulation
7. Open a pull request to this repository.

Your contribution will provide users with a practical understanding of file manipulation in Python. Thank you for creating this useful Python program for our repository!