Python provides several methods to read data from files. Before reading a file, it must be opened in read mode (r).
Open a File for Reading
Syntax
file = open("file_name.txt", "r")
Example
file = open("sample.txt", "r")
print(file.read())
file.close()
Output:
Hello Python
Welcome to File Handling
read()
The read() method reads the entire file content.
Example
file = open("sample.txt", "r")
content = file.read()
print(content)
file.close()
Output:
Hello Python
Welcome to File Handling
Read Specific Characters
You can specify the number of characters to read.
Example
file = open("sample.txt", "r")
print(file.read(5))
file.close()
Output:
Hello
readline()
The readline() method reads one line at a time.
Example
file = open("sample.txt", "r")
print(file.readline())
file.close()
Output:
Hello Python
Read Multiple Lines
Example
file = open("sample.txt", "r")
print(file.readline())
print(file.readline())
file.close()
Output:
Hello Python
Welcome to File Handling
readlines()
The readlines() method reads all lines and returns them as a list.
Example
file = open("sample.txt", "r")
print(file.readlines())
file.close()
Output:
['Hello Python\n', 'Welcome to File Handling']
Loop Through a File
Example
file = open("sample.txt", "r")
for line in file:
print(line)
file.close()
Output:
Hello Python
Welcome to File Handling
Using with Statement
Using with automatically closes the file after use.
Example
with open("sample.txt", "r") as file:
print(file.read())
Output:
Hello Python
Welcome to File Handling
Read File Line by Line
Example
with open("sample.txt", "r") as file:
for line in file:
print(line.strip())
Output:
Hello Python
Welcome to File Handling
Summary
- Open a file in read mode using
"r". read()reads the entire file.read(n)reads a specific number of characters.readline()reads one line at a time.readlines()returns all lines as a list.- Files can be read using loops.
- The
withstatement automatically closes the file. - Always close files when not using the
withstatement.