Online Base64 Encoder

Base64 encode can be achieved by

$ echo Some_data_to_be_converted | base64U29tZV9kYXRhX3RvX2JlIF9jb252ZXJ0ZWQK

And Base64 decode can be achieved by

$ echo U29tZV9kYXRhX3RvX2JlIF9jb252ZXJ0ZWQK | base64 -dSome_data_to_be_converted

1. How to achieve Base64URL encode/decode?

2. Is it just enough to replace "+" with "-" and "/" with " _" ?

3. When to do the padding "#"(adding/remove "#" to be considered )?

There's a way to encode/decode a string to/from Base64 without having the padding at the end? I mean the '==' ending.

I'm using base64.URLEncoding.EncodeToString to encode and it works perfectly but I didn't see a way to decide to not use the padding at the end ( like on java ).

I´m using a .NET core 3.0 project on Windows 10. I´m trying to encode a string to base64 with below code:

var stringvalue = "Row1" + Environment.NewLine + "\n\n" + "Row2";var encodedString = Convert.ToBase64String(Encoding.UTF8.GetBytes(stringvalue));

encodedString has then below result:

Um93MQ0KCgpSb3cy

stringvalue is:

Row1\r\n\n\nRow2

However, if I´m passing the same value to this site (https://www.base64encode.org/), i´m getting another result:

Um93MVxyXG5cblxuUm93Mg==

In visual studio, I tried to resave the file with Unix lineendings, but without any luck:

I want the string to be encoded as how it´s done in https://www.base64encode.org. Any ideas how to get this done?

I want to achieve Base64 URL safe encoding in C#. In Java, we have the common Codec library which gives me an URL safe encoded string. How can I achieve the same using C#?

byte[] toEncodeAsBytes = System.Text.ASCIIEncoding.ASCII.GetBytes("StringToEncode");string returnValue = System.Convert.ToBase64String(toEncodeAsBytes);

The above code converts it to Base64, but it pads ==. Is there is way to achieve URL safe encoding?

What is the purpose of padding in base64 encoding. The following is the extract from wikipedia:

"An additional pad character is allocated which may be used to force the encoded output into an integer multiple of 4 characters (or equivalently when the unencoded binary text is not a multiple of 3 bytes) ; these padding characters must then be discarded when decoding but still allow the calculation of the effective length of the unencoded text, when its input binary length would not be not a multiple of 3 bytes (the last non-pad character is normally encoded so that the last 6-bit block it represents will be zero-padded on its least significant bits, at most two pad characters may occur at the end of the encoded stream)."

I wrote a program which could base64 encode any string and decode any base64 encoded string. What problem does padding solves?