Ok so I have a string of text, encoded in Base 64 like below:
string myText = "abcBASE64TEXTGOESHEREdef=="; // actual string is 381 characters long with trailing '=='
I then convert my string from Base 64 to a byte array like so:
byte[] decodedFromBase64 = Convert.FromBase64String(myText);
At this point, I want to get the string value of this byte array and save this in a text file without data loss or corruption. The code below doesn't seem to be doing it:
string myDecodedText = Encoding.ASCII.GetString(decodedFromBase64);
StreamWriter myStreamWriter = new StreamWriter("C:\\OpenSSL-Win32\\bin\\textToDecrypt.txt");
myStreamWriter.Write(myString);
myStreamWriter.Flush();
myStreamWriter.Close();
Can somebody please tell me where I'm going wrong.
Edit: The output is unreadable, I need to take the decoded string and then use OpenSSL to decrypt it. The Output and the result from OpenSSL are both below:
To decode a file with contents that are base64 encoded, you simply provide the path of the file with the --decode flag. As with encoding files, the output will be a very long string of the original file. You may want to output stdout directly to a file.
In JavaScript there are two functions respectively for decoding and encoding Base64 strings: btoa() : creates a Base64-encoded ASCII string from a "string" of binary data ("btoa" should be read as "binary to ASCII"). atob() : decodes a Base64-encoded string ("atob" should be read as "ASCII to binary").
The ToBase64String method is designed to process a single byte array that contains all the data to be encoded. To encode data from a stream, use the System. Security.
In base64 encoding, the character set is [A-Z, a-z, 0-9, and + /] . If the rest length is less than 4, the string is padded with '=' characters. ^([A-Za-z0-9+/]{4})* means the string starts with 0 or more base64 groups.
public static string base64Decode(string data)
{
byte[] toDecodeByte = Convert.FromBase64String(data);
System.Text.UTF8Encoding encoder = new System.Text.UTF8Encoding();
System.Text.Decoder utf8Decode = encoder.GetDecoder();
int charCount = utf8Decode.GetCharCount(toDecodeByte, 0, toDecodeByte.Length);
char[] decodedChar = new char[charCount];
utf8Decode.GetChars(toDecodeByte, 0, toDecodeByte.Length, decodedChar, 0);
string result = new String(decodedChar);
return result;
}
static void Main(string[] args)
{
string completeUrl = SERVICE_URL;
WebRequest request = WebRequest.Create(completeUrl);
request.Credentials = CredentialCache.DefaultCredentials;
WebProxy proxyObject = new WebProxy(SERVICE_URL, true);
request.Proxy = proxyObject;
HttpWebResponse webResponse = (HttpWebResponse)request.GetResponse();
byte[] data;
const int BUFFER_SIZE = 2048;
int bytesRead;
byte[] buffer = new byte[BUFFER_SIZE];
using (MemoryStream mss = new MemoryStream())
{
using (BinaryReader readers = new
BinaryReader(webResponse.GetResponseStream(), System.Text.Encoding.UTF8))
{
while ((bytesRead = readers.Read(buffer, 0, BUFFER_SIZE)) > 0)
{
mss.Write(buffer, 0, bytesRead);
}
data = mss.ToArray();
System.Text.Encoding enc = System.Text.Encoding.GetEncoding("iso-8859-1");
string str = enc.GetString(data);
XmlDocument xdoc = new XmlDocument();
xdoc.LoadXml(str);
XmlNode xmlList = xdoc.ChildNodes[1];
XmlNode item = xmlList.ChildNodes[1]; //this is your data : JVBERi0xLjUNCiXNzc3NDQoxIDAgb2JqDQo8PA0KL0NyZWF0b3IgKERvY3VtZW50UHJ
Base64Decode(item.InnerText.ToString());
Console.WirteLine("File successfully saved");
Console.ReadLine();
}
}
}
public static void Base64Decode(string base64EncodedData)
{
var base64EncodedBytes = System.Convert.FromBase64String(base64EncodedData);
File.WriteAllBytes("pdf.pdf", base64EncodedBytes);
}
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With