Caesar Cipher Project in Python

Caesar Cipher Project in Python

Simple Caesar Cipher encryptor and decryptor built with python. Caesar Cipher Technique is the simple and easy method of encryption technique. It is simple type of substitution cipher. Each letter of plain text is replaced by a letter with some fixed number of positions down with alphabet.

Caesar Cipher Project Python

The script was created with Python3 and the built-in functions in it. Follow the below steps

Step 1. Download Python

You only need Python to run this script. You can visit here to download Python.

Step 2. Write the following code

Write this code in a Python file or directly copy this code and save the file with the name and .py extension python caesarcypher.py

class main:
def __init__(self,key:dict) -> None:
self.key = key

def get_input(self) -> None:
while True:
blank_string = str(input("Enter string to decrypt: "))
if blank_string.isalpha():
blank_string = blank_string.lower()
self.blank_string = blank_string
break
else:
print("Input is not valid")
continue

def encrypt_string(self) -> str:
output = ""
for c in self.blank_string:
for k,v in self.key.items():
if k == c:
output += v
else:
continue
self.decrypted_string = output
return(output)

def decrypt_string(self, string: str) -> str:
output = ""
string = string.lower()
string = string.strip()
if string == "":
return(self.blank_string)
else:
for c in string:
for k,v in self.key.items():
if v == c:
output += k

return(output)

if __name__ == "__main__":
key ={"a": "d", "b": "e", "c": "f", "d": "g", "e": "h", "f": "i", "g": "j", "h": "k", "i": "l", "j": "m", "k": "n", "l": "o", "m": "p", "n": "q", "o": "r", "p": "s", "q": "t", "r": "u", "s": "v", "t": "w", "u": "x", "v": "y", "w": "z", "x": "a", "y": "b", "z": "c"}
main = main(key=key)
main.get_input()
print(main.encrypt_string())

Step 3. Run the code

After saving the code double-click on the file to run the program or simply open Command Prompt and write the following command and string to decrypt.

python3 caesarcypher.py
Enter string to decrypt: hello
khoor

Demo: