How to bring back removed spaces from a string

Question

I have windows form application that encrypt the string and decrypt it back using Caesar Algorithm. When encrypting a string I have to remove spaces from it ,but when I'll decrypt it again I should bring back the removed spaces into their actual places.

The problem I faced in this case is in bringing the removed spaces from the encrypted string and also when decrypting there are some letters are changed into special characters like this pattern where the encryption key is 3:

Plain text: My name is Shafaq Zahir
Encrypted text: PbqdphlvVkdidtCdklu
Decrypted text: M_nameisShafaq@ahir

This is my code

class CaesarAlgorithm
    {
        public string Encrypt(string pt,int key)
        {
            char[] buffer = pt.Replace(" ",string.Empty).ToCharArray();
            //char[] buffer = pt.ToCharArray();
            for(int i=0;i<buffer.Length;i++)
            {
                if (buffer[i] >= 'a' && buffer[i] <= 'z')
                {
                    buffer[i] = (char)(buffer[i] + key);
                    if (buffer[i] > 'z')
                    {
                        buffer[i] = (char)(buffer[i] - 26);
                    }
                }
                else if (buffer[i] >= 'A' && buffer[i] <= 'Z')
                {
                    buffer[i] = (char)(buffer[i] + key);
                    if (buffer[i] > 'Z')
                    {
                        buffer[i] = (char)(buffer[i] - 26);
                    }
                }
            }

            return new string (buffer);

        }

        public string Decrypt(string pt,int key)
        {
            char[] buffer = pt.ToCharArray();
            for (int i = 0; i < buffer.Length; i++)
            {
                if (buffer[i] >= 'a' && buffer[i] <= 'z')
                {
                    buffer[i] = (char)(buffer[i] - key);
                    if (buffer[i] > 'z')
                    {
                        buffer[i] = (char)(buffer[i] - 26);
                    }
                }
                else if (buffer[i] >= 'A' && buffer[i] <= 'Z')
                {
                    buffer[i] = (char)(buffer[i] - key);
                    if (buffer[i] > 'Z')
                    {
                        buffer[i] = (char)(buffer[i] - 26);
                    }
                }
            }

            return new string(buffer);
        }
    }
}

I believe your functions should better be called "ObfuscateAndDestruct" and "PartiallyReconstructWithFaults", because that is what they do. Never try to invent 'encryption' yourself, always find a library that does it well without making beginner mistakes. — Peter B

colby brooks colby brooks · Accepted Answer · 2017-07-05T13:47:09

The only thing I can think of right would be to loop through the original char array and save the index of each space then add it back the end, kinda just woke up so there's probably a better solution. Also just wondering why you can't have spaces

How to bring back removed spaces from a string

2 Answers