File Handling

Python file handling is a powerful tool that allows you to read, write, and manipulate files.

Opening a file

To open a file in Python, you use the open() function. The open() function takes two arguments: the path to the file and the mode in which to open the file.

The mode specifies how the file will be opened. The following are some common modes:

• r: Open the file for reading.
• w: Open the file for writing. If the file does not exist, it will be created.
• a: Open the file for appending. If the file does not exist, it will be created.

Example:

 

Python

# Open the file "myfile.txt" for reading
f = open("myfile.txt", "r")
 

Reading from a file

To read from a file, you can use the read() method. The read() method returns the contents of the file as a string.

Example:

 

Python

# Read the contents of the file "myfile.txt"
contents = f.read()

# Print the contents of the file
print(contents)
 

Writing to a file

To write to a file, you can use the write() method. The write() method takes a string as an argument and writes it to the file.

Example:

 

Python

# Open the file "myfile.txt" for writing
f = open("myfile.txt", "w")

# Write the string "Hello, world!" to the file
f.write("Hello, world!")

# Close the file
f.close()
 

Appending to a file

To append to a file, you can use the append() method. The append() method takes a string as an argument and appends it to the end of the file.

Example:

 

Python

# Open the file "myfile.txt" for appending
f = open("myfile.txt", "a")

# Append the string "This is a new line of text." to the file
f.write("This is a new line of text.")

# Close the file
f.close()
 

Closing a file

Once you have finished reading from or writing to a file, you should close it. This will release the file resources and ensure that the data in the file is saved.

Example:

 

Python

# Open the file "myfile.txt" for reading
f = open("myfile.txt", "r")

# Read the contents of the file
contents = f.read()

# Close the file
f.close()
 

Conclusion

Python file handling is a powerful tool that allows you to read, write, and manipulate files. By understanding how to use file handling, you can write more efficient and robust code.