Python Tutorial - File Operation

1. Open a File
2. Close a File
3. File Object
4. Write a File
5. Read a File
6. Rename and Remove a File

In this section, you will learn how to perform operations on files in Python programming.

Using Python you can open a file, read or write something to a file and then close a file. This can be done by using some file manipulating functions. To perform any operation on a file you have to create an object of the file first.

Open a File

A file can be opened using open() function. A file object is created which is later used to perform operations on the file.

The syntax to open a file is as follows:

obj = open(fileName, mode)

fileName is the name of the file, mode defines the mode in which the file will be opened for example r to open a file in reading mode.

fobj = open("PythonExamplefile.txt", "r")

The file PythonExamplefile will be opened in read mode.

Modes to Open a File

Close a File

After performing operations on a file, a file must be closed. The close() method is used to close a file.

fobj.close()

fobj = open("PythonExamplefile.txt", "r")
# operations on file
fobj.close()

File Object

When a file is opened, a file object is created which can be used to perform operations. For example, you can get information about a file such as its name, the mode in which the file is opened, etc.

fobj = open("PythonExamplefile.txt", "r")
print("File name", fobj.name)
print("File mode", fobj.mode)
fobj.close()

Result:

File name PythonExamplefile.txt
File mode r

Write a File

The write() method is used write something on a file. The file must be opened to write on.

The syntax to use write() method is as follows:

fobj.write("string")

Example:

fobj = open("PythonExamplefile.txt", "w")
fobj.write("Hello Python Programming")
fobj.close()

The following content will be written to the file:

Hello Python Programming

Read a File

You can read from a file by using the read() method. Reading from a file is getting input from the file.

The following is the syntax to read from a file:

fobj.read(numberofBytes)

Here numberofBytes is the total number of bytes that are read from the file.

fobj = open("PythonExamplefile.txt", "r")
content = fobj.read(5)
print(content)
fobj.close()

Hello

Rename and Remove a File

Rename a File

The rename() method is used to rename a file.

The syntax of rename() is as follows:

os.rename(currentName, newName)

Here os is a module which lets you perform functions that are Operating System dependent.

Example:

import os

os.rename("PythonExamplefile.txt", "Python.txt")

The new name of the file is Python.txt now.

Remove a File

A file is deleted by using remove() method.

The syntax of remove() is as follows:

os.remove(nameofFile)

Example:

import os

os.remove("Python.txt")