140byt.es - Base64 Encoder

140byt.es - Base64 Encoder

# 140byt.es - Base64 Encoder

A simple base64 encoder. Simply pass your string and a reference to the function to get back the encoded string.


### Example

    var 
      map ="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
      sample = "140bytes rocks!",
      encoded = base64Encode(sample, map);

### Acknowledgment

Artur Honzawa [@arturhonzawa](http://twitter.com/arturhonzawa) hacked the [main code](https://gist.github.com/988729) and further compression was done by me ([@aemkei](http://twitter.com/aemkei)). Thanks to Rob Griffiths [@bytespider](http://twitter.com/bytespider) and Jed Schmidt [@jedschmidt](http://twitter.com/jedschmidt) for some pretty good hints!

### Issues

* Proper "=" padding does not work
* IE's JScript fails with the RegExp
* Doesn't encode null bytes


Feel free to fork and improve!

annotated.js

var base64Encode = function(
  a, // input string
  b, // map string
  c, // placeholder
  d, // placeholder
  e, // placeholder
  f, // placeholder
  g // placeholder
){

  for(
    g = c = e = "";
    (d = a.charCodeAt(g)) && 
    (c += /.{8}$/(
      1e7 + // make sure leading zeroes are there
      d.toString(2) // convert to binary
    )),
    f = c.substr(g++ * 6, 6); // pick bits in groups of 6
  ) e += b[parseInt(f, 2)]; // build result string

  return e
}

index.js

function(a,b,c,d,e,f,g){for(g=c=e="";(d=a.charCodeAt(g))&&(c+=/.{8}$/(1e7+d.toString(2))),f=c.substr(g++*6,6);)e+=b[parseInt(f,2)];return e}

package.json

{

  "name": "Base64Encoder",

  "description": "A JavaScript Base64 encoder in 140 Bytes.",

  "contributors": [
    { 
      "name" : "Artur Honzawa", 
      "url" : "https://github.com/arturh"
    },
    { 
      "name" : "Martin Kleppe", 
      "url" : "https://github.com/aemkei"
    }
  ],

  "keywords": [
    "base64",
    "encode"
  ]
}