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read(), readlines() and other methods in Python



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read(), readlines() and Other Methods in Python

Python provides several methods to read from and manipulate files. Here are some common methods:

1. read()

The read() method reads the entire content of a file and returns it as a string.


# Open the file in read mode
with open('example.txt', 'r') as file:
    # Read the entire content of the file
    content = file.read()
    print(content)

2. readlines()

The readlines() method reads all the lines of a file and returns a list where each element is a line in the file.


# Open the file in read mode
with open('example.txt', 'r') as file:
    # Read all lines of the file
    lines = file.readlines()
    for line in lines:
        print(line.strip())  # strip() removes the newline character

3. readline()

The readline() method reads one line from the file and returns it as a string.


# Open the file in read mode
with open('example.txt', 'r') as file:
    # Read the first line of the file
    first_line = file.readline()
    print(first_line)

4. write()

The write() method writes a string to the file. If the file is opened in write or append mode, it will create the file if it does not exist.


# Open the file in write mode
with open('example.txt', 'w') as file:
    # Write a string to the file
    file.write('Hello, World!')

5. writelines()

The writelines() method writes a list of strings to the file. Each string in the list will be written as a line in the file.


# Open the file in write mode
with open('example.txt', 'w') as file:
    # Write a list of strings to the file
    lines = ['Hello, World!\n', 'Python is great!\n']
    file.writelines(lines)

6. close()

The close() method closes the file. It is a good practice to always close the file after performing operations on it. Using the with statement as shown above is recommended as it handles closing the file automatically.


# Open the file in read mode
file = open('example.txt', 'r')

# Perform file operations
content = file.read()
print(content)

# Close the file
file.close()
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