invalid length for a base 64 char array

[vbbit]

Hi I have a code below, but everytime, my "text" throwing an error invalid length for a base 64 char array, and I don't know how to fix this.

try
            {
                key = Encoding.UTF8.GetBytes(stringKey.Substring(0, 8));
                DESCryptoServiceProvider des = new DESCryptoServiceProvider();
                Byte[] byteArray = Convert.FromBase64String(text);
                MemoryStream memoryStream = new MemoryStream();
                CryptoStream cryptoStream = new CryptoStream(memoryStream,
                    des.CreateDecryptor(key, IV), CryptoStreamMode.Write);
                cryptoStream.Write(byteArray, 0, byteArray.Length);
                cryptoStream.FlushFinalBlock();
                return Encoding.UTF8.GetString(memoryStream.ToArray());
            }
            catch (Exception ex)
            {
                // Handle Exception Here
            }
            return string.Empty;

[vbbit]

Turned out there's a "+" sign in my string, but how to get rid of it? If I put any other characters, it will screw up my string though.

[mendhak]

The proper way to get rid of it is to tackle it at its source. If it's coming in from a database then figure out what's putting it there and get that application to do it right.

The improper way is to perform a .Replace(), replacing the + with an empty string, but that doesn't guarantee future problems in the base64 string, since other characters may get introduced in there.