topherPedersen's Hexadecimal Conversion Tool

hex_conversion_tool.py

# topherPedersen's Hexadecimal Conversion Tool
import codecs

print("topherPedersen's Hexadecimal Conversion Tool")
print("")
print("Enter Text to be Converted to Hexadecimal Format")
print("<VALID CHARACTERS: 0-9, a-f>")
# prompt user to enter string to be converted
string_to_be_converted = input(">>> ")

# handle potential errors
error_found = False
error_message = []
# check to make sure the user has entered an even number of characters
if len(string_to_be_converted) % 2 > 0:
    error_found = True
    error_message.append("ERROR: Please enter an even number of characters")
# loop through characters to check for invalid characters
# note, only characters 0-9 and a-f are valid
for i, c in enumerate(string_to_be_converted):
    valid_character_identified = False
    if c == "0":
        valid_character_identified = True    
    elif c == "1":
        valid_character_identified = True
    elif c == "2":
        valid_character_identified = True    
    elif c == "3":
        valid_character_identified = True
    elif c == "4":
        valid_character_identified = True    
    elif c == "5":
        valid_character_identified = True
    elif c == "6":
        valid_character_identified = True    
    elif c == "7":
        valid_character_identified = True
    elif c == "8":
        valid_character_identified = True    
    elif c == "9":
        valid_character_identified = True
    elif c == "a":
        valid_character_identified = True    
    elif c == "b":
        valid_character_identified = True
    elif c == "c":
        valid_character_identified = True    
    elif c == "d":
        valid_character_identified = True
    elif c == "e":
        valid_character_identified = True    
    elif c == "f":
        valid_character_identified = True

    if valid_character_identified == False:
        error_found = True
        error_message.append("ERROR: Invalid character entered")
        break

# if no errors are found, convert to hexadecimal and print output to console
if error_found == False:
    # convert string to hexadecimal
    hexadecimal = codecs.decode(string_to_be_converted, 'hex')
    # output hexadecimal to the console
    print("")
    print("Hexadecimal Output: " + str(hexadecimal))
else:
    # loop through list of error messages and print errors to console
    for error in error_message:
        print(error)