Java Script - Base64 Encoding/Decoding

// Create Base64 Object
var Base64={_keyStr:"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",encode:function(e)

{var t=""; var n,r,i,s,o,u,a; var f=0; e=Base64._utf8_encode(e); while(f<e.length){n=e.charCodeAt(f++); r=e.charCodeAt(f++); i=e.charCodeAt(f++); s=n>>2; o=(n&3)<<4|r>>4; u=(r&15)<<2|i>>6; a=i&63; if(isNaN(r)){u=a=64} else if(isNaN(i)){a=64}t=t+this._keyStr.charAt(s)+this._keyStr.charAt(o)+this._keyStr.charAt(u)+this._keyStr.charAt(a)} return t},decode:function(e){ var t=""; var n,r,i; var s,o,u,a; var f=0; e=e.replace(/[^A-Za-z0-9\+\/\=]/g,""); while(f<e.length {s=this._keyStr.indexOf(e.charAt(f++)); o=this._keyStr.indexOf(e.charAt(f++)); u=this._keyStr.indexOf(e.charAt(f++)); a=this._keyStr.indexOf(e.charAt(f++)); n=s<<2|o>>4; r=(o&15)<<4|u>>2; i=(u&3)<<6|a; t=t+String.fromCharCode(n); if(u!=64){t=t+String.fromCharCode(r)} if(a!=64){t=t+String.fromCharCode(i)} }t=Base64._utf8_decode(t); return t},_utf8_encode:function(e){e=e.replace(/\r\n/g,"\n"); var t=""; for(var n=0; n<e.length;n++){ var r=e.charCodeAt(n); if(r<128){ t+=String.fromCharCode(r)}else if(r>127&&r<2048){t+=String.fromCharCode(r>>6|192); t+=String.fromCharCode(r&63|128)}

else{t+=String.fromCharCode(r>>12|224);

t+=String.fromCharCode(r>>6&63|128); t+=String.fromCharCode(r&63|128)}}return t},_utf8_decode:function(e){ var t=""; var n=0; var r=c1=c2=0; while(n<e.length){r=e.charCodeAt(n); if(r<128){t+=String.fromCharCode(r); n++}

else if(r>191&&r<224){c2=e.charCodeAt(n+1);

t+=String.fromCharCode((r&31)<<6|c2&63); n+=2}else{c2=e.charCodeAt(n+1); c3=e.charCodeAt(n+2); t+=String.fromCharCode((r&15)<<12|(c2&63)<<6|c3&63); n+=3}}return t}}

// Define the string
var string = 'Hello World!';

// Encode the String
var encodedString = Base64.encode(string);
console.log(encodedString); // Outputs: "SGVsbG8gV29ybGQh"

// Decode the String
var decodedString = Base64.decode(encodedString);
console.log(decodedString); // Outputs: "Hello World!"

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