phpjs/functions/strings/ord.js

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function ord(string) {
  //  discuss at: http://phpjs.org/functions/ord/
  // original by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
  // bugfixed by: Onno Marsman
  // improved by: Brett Zamir (http://brett-zamir.me)
  //    input by: incidence
  //   example 1: ord('K');
  //   returns 1: 75
  //   example 2: ord('\uD800\uDC00'); // surrogate pair to create a single Unicode character
  //   returns 2: 65536

  var str = string + '',
    code = str.charCodeAt(0);
  if (0xD800 <= code && code <= 0xDBFF) { // High surrogate (could change last hex to 0xDB7F to treat high private surrogates as single characters)
    var hi = code;
    if (str.length === 1) {
      return code; // This is just a high surrogate with no following low surrogate, so we return its value;
      // we could also throw an error as it is not a complete character, but someone may want to know
    }
    var low = str.charCodeAt(1);
    return ((hi - 0xD800) * 0x400) + (low - 0xDC00) + 0x10000;
  }
  if (0xDC00 <= code && code <= 0xDFFF) { // Low surrogate
    return code; // This is just a low surrogate with no preceding high surrogate, so we return its value;
    // we could also throw an error as it is not a complete character, but someone may want to know
  }
  return code;
}