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js decode base64

let str = 'bmltZXNoZGV1amEuY29t';
let buff = new Buffer(str, 'base64');
let base64ToStringNew = buff.toString('utf8');

javascript encode base64

const encoded = window.btoa('Alireza Dezfoolian'); // encode a string
const decoded = window.atob(encoded); // decode the string

js base64 encoding

str = "The quick brown fox jumps over the lazy dog";
b64 = btoa(unescape(encodeURIComponent(str)));
str = decodeURIComponent(escape(window.atob(b64)));

base64 encode in javascript

const base64Encode = (string) => {
  const newText = btoa(string);
  return newText;
};

js base64 encode

function toBinary(string) {
  const codeUnits = new Uint16Array(string.length);
  for (let i = 0; i < codeUnits.length; i++) {
    codeUnits[i] = string.charCodeAt(i);
  }
  return String.fromCharCode(...new Uint8Array(codeUnits.buffer));
}

function fromBinary(binary) {
  const bytes = new Uint8Array(binary.length);
  for (let i = 0; i < bytes.length; i++) {
    bytes[i] = binary.charCodeAt(i);
  }
  return String.fromCharCode(...new Uint16Array(bytes.buffer));
}

const myString = "☸☹☺☻☼☾☿"
// console.log(btoa(myString)) // Error InvalidCharacterError: The string to be encoded contains characters outside of the Latin1 range.
const converted = toBinary(myString)
const encoded = btoa(converted)
console.log(encoded)

const decoded = atob(encoded)
const original = fromBinary(decoded)
console.log(original);

base64 in js

const Base64 = {
    _keyStr: "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=",
    encode: function(input: string) {
        let output = "";
        let chr1, chr2, chr3, enc1, enc2, enc3, enc4;
        let i = 0;

        input = Base64._utf8_encode(input);

        while (i < input.length) {

            chr1 = input.charCodeAt(i++);
            chr2 = input.charCodeAt(i++);
            chr3 = input.charCodeAt(i++);

            enc1 = chr1 >> 2;
            enc2 = ((chr1 & 3) << 4) | (chr2 >> 4);
            enc3 = ((chr2 & 15) << 2) | (chr3 >> 6);
            enc4 = chr3 & 63;

            if (isNaN(chr2)) {
                enc3 = enc4 = 64;
            } else if (isNaN(chr3)) {
                enc4 = 64;
            }

            output = output + this._keyStr.charAt(enc1) + this._keyStr.charAt(enc2) + this._keyStr.charAt(enc3) + this._keyStr.charAt(enc4);

        }

        return output;
    },
    _utf8_encode: function(input: string) {
        input= input.replace(/
/g, "
");
        let utftext = "";

        for (let n = 0; n < input.length; n++) {

            let c = input.charCodeAt(n);

            if (c < 128) {
                utftext += String.fromCharCode(c);
            }
            else if ((c > 127) && (c < 2048)) {
                utftext += String.fromCharCode((c >> 6) | 192);
                utftext += String.fromCharCode((c & 63) | 128);
            }
            else {
                utftext += String.fromCharCode((c >> 12) | 224);
                utftext += String.fromCharCode(((c >> 6) & 63) | 128);
                utftext += String.fromCharCode((c & 63) | 128);
            }

        }

        return utftext;
    },

}


const encode = ( cipher : string) => {

    const encodedString: string = Base64.encode(cipher)

    return encodedString;
}

base64 to base64url javascript

/**
 * Function that converts a base64 string into a base64url string
 * @param {string} input - The string to convert
 */
function base64ToBase64url(input) {
  // Replace non-url compatible chars with base64url standard chars and remove leading =
  return input
    .replace(/+/g, '_')
    .replace(///g, '-')
    .replace(/=+$/g, '');
}