FILE HANDLING PART -2

Close Files

It is a good practice to always close the file when you are done with it.

Example

Close the file when you are finish with it:

f = open("demofile.txt", "r")
print(f.readline())
f.close()

 

C:\Users\My Name>python demo_file_close.py
Hello! Welcome to demofile.txt

 

Python FileWrite

 

Write to an Existing File

To write to an existing file, you must add a parameter to the open() function:

"a" - Append - will append to the end of the file

"w" - Write - will overwrite any existing content

Example

Open the file "demofile2.txt" and append content to the file:

f = open("demofile2.txt", "a")
f.write("Now the file has more content!")
f.close()

#open and read the file after the appending:
f = open("demofile2.txt", "r")
print(f.read())

C:\Users\My Name>python demo_file_append.py
Hello! Welcome to demofile2.txt
This file is for testing purposes.
Good Luck!Now the file has more content!

Example

Open the file "demofile3.txt" and overwrite the content:

f = open("demofile3.txt", "w")
f.write("Woops! I have deleted the content!")
f.close()

#open and read the file after the appending:
f = open("demofile3.txt", "r")
print(f.read())

C:\Users\My Name>python demo_file_write.py
Woops! I have deleted the content!

 

Create a New File

 

To create a new file in Python, use the open() method, with one of the following parameters:

"x" - Create - will create a file, returns an error if the file exist

"a" - Append - will create a file if the specified file does not exist

"w" - Write - will create a file if the specified file does not exist

Example

Create a file called "myfile.txt":

f = open("myfile.txt", "x")

Result: a new empty file is created!

Example

Create a new file if it does not exist:

f = open("myfile.txt", "w")

 

 

Python Delete File

To delete a file, you must import the OS module, and run its os.remove() function:

Example

Remove the file "demofile.txt":

import os
os.remove("demofile.txt")

---

Check if File exist:

To avoid getting an error, you might want to check if the file exists before you try to delete it:

Example

Check if file exists, then delete it:

import os
if os.path.exists("demofile.txt"):
  os.remove("demofile.txt")
else:
  print("The file does not exist")

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Delete Folder

To delete an entire folder, use the os.rmdir() method:

Example

Remove the folder "myfolder":

import os
os.rmdir("myfolder")