CPT 341 VB.NET Project 2 – Symmetric Key Encryption VB. Topics: Simple Encryptio

Question

CPT 341 VB.NET Project 2 – Symmetric Key Encryption

VB. Topics: Simple Encryption/Decryption, Multiple Forms, String Manipulation & Conversion, File I/O, Readline, WriteLine, Sequential Text File, ASCII Character Set, OpenFileDialog, SaveFileDialog, PasswordChar, Form.Show , Me.Hide, Chr(), Asc(), Chr(), Mod Operator

Develop a Visual Basic Windows Forms application using 3 VB Forms that will ‘encrypt’ (character shift) the characters in a string based on a password (symmetric key) and store the cipher-text in a text file. The application must also open (‘decrypt’) the message only using the password that was used to encrypt the message.

Form 1 – Enter a message in the “Enter Text to Encrypt” TextBox control. Use Textbox controls to either encrypt or decrypt a message. A separate VB Form should be used for the encryption/decryption events.

Password Form – Enter a password (and again to confirm the password) to be used to convert the clear-text message to cipher-text. The cipher-text will need to written to a sequential text-file. Use a SaverFileDialog control to save the cipher-text message.

Decrypt Form – Use the password (used to create the cipher-text) to decrypt the cipher-text stored in the sequential text file. To locate the file containing the cipher-text, use an OpenFileDialog control.

Notes

Use File.IO to read and write text files

Passwords will need to be converted to numbers before storing each value in an array

Since there are a limited number of digits in a key, your program must ‘wrap-back’ to the first digit

The numeric equivalent of the password must be stored in an array

The resulting cipher-text output is to be stored in a text file

Using the same password for encryption and decryption Since only printable characters are used (see table), if the ASCII code becomes larger than 126, you will need to wrap around to the ASCII code 32 (space)

Use exception handling where needed…for example, FileNotFound or DirectoryNotFound.   

‘Shifting Characters’ Example: Using a sample password = “Pwdabc”, the numeric equivalent of each character is equal to 80119100979899

Explanation / Answer

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#ifndef DICE_H
#define DICE_H

class Dice
;
#endif

Here is that the ccp file for dice.cpp

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#include<cstdlib>
#include<ctime>
#include "Dice.h"

using namespace std;

Dice::Dice(int numSides)
unsigned seed = time (0);
   srand(seed);
   sides = numSides;
   roll();
  

}

void Dice::roll()

worth = (rand() the troubles (sides - MIN_VALUE +1 ))+MIN_VALUE;

}

int Dice::getSides()

int Dice::getValue()
  

and finally here is my ASCII text file cpp

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#include<iostream>
#include"Dice.h"
#include<string>

using namespace std;

int main()

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