Javascript: encode(decode) html text into html entity

htmlentity.js

// encode(decode) html text into html entity
var decodeHtmlEntity = function(str) {
  return str.replace(/&#(\d+);/g, function(match, dec) {
    return String.fromCharCode(dec);
  });
};

var encodeHtmlEntity = function(str) {
  var buf = [];
  for (var i=str.length-1;i>=0;i--) {
    buf.unshift(['&#', str[i].charCodeAt(), ';'].join(''));
  }
  return buf.join('');
};

var entity = '高级程序设计';
var str = '高级程序设计';
console.log(decodeHtmlEntity(entity) === str);
console.log(encodeHtmlEntity(str) === entity);
// output:
// true
// true

Works well for encoding input from text fields straight into html using jQuery and this.

Thanks, this solved an annoying issue with .net localization.

I've written a little bit better implementation of decodeHtmlEntity that accept's html entities by name Gist

Thank you!

with Unicode support (\uWXYZ):

function encodeHtmlEntity(str) {
  return str.replace(/[\u00A0-\u9999\<\>\&\'\"\\\/]/gim, function(c){
    return '&#' + c.charCodeAt(0) + ';' ;
  });
}

or as bookmarklet (placed in your bookmark-toolbar to use whenever..)

javascript:(function(){prompt("output:",prompt("∞ to HTML-Entity:","<div>❝Likė A Ƀoŝš❞ ©®</div>").replace(/[\u00A0-\u9999\<\>\&\'\"\\\/]/gim,function(c){return '&#'+c.charCodeAt(0)+';'}));return true;}());

_{sorry about the watermark, I've took it from here}

Thanks so much. I just used it.

Thanks a lot for this!
What if my string also has hexadecimal along with decimal values?

function encodeHtmlEntity(str) {
  var buf = '';
  for (var i=0; i < str.length; i++) {
    buf += '&#'+ str.charCodeAt(i) + ';';
  }
  return buf;
};

Don't construct an array just to join it with empty string.

Thank you

Thank you for nice one

Thank You. It was good of you to post it.

Thanks!

TypeScript version:

const decodeHtmlEntity = function (str: string) {
  return str.replace(/&#(\d+);/g, function (match: string, dec: number) {
    return String.fromCharCode(dec)
  })
}

const encodeHtmlEntity = function (str: string) {
  const buf = []
  for (let i = str.length - 1; i >= 0; i--) {
    buf.unshift(['&#', str.charCodeAt(i), ';'].join(''))
  }
  return buf.join('')
}

simple and useful

How about ", it doesn't decode it to "