Javascript String toJSONString()

//--// w w w .  j  a v  a2s. co  m
//-- Deprecated String functions
//--

// @Deprecated: no direct replacement, since not used in core code
String.prototype.toJSONString = function()
{
 // Convert a string to it's JSON representation by encoding control characters, double quotes and backslash. See json.org
 var m = {
  '\b': '\\b',
  '\f': '\\f',
  '\n': '\\n',
  '\r': '\\r',
  '\t': '\\t',
  '"' : '\\"',
  '\\': '\\\\'
  };
 var replaceFn = function(a,b) {
  var c = m[b];
  if(c)
   return c;
  c = b.charCodeAt();
  return '\\u00' + Math.floor(c / 16).toString(16) + (c % 16).toString(16);
  };
 if(/["\\\x00-\x1f]/.test(this))
  return '"' + this.replace(/([\x00-\x1f\\"])/g,replaceFn) + '"';
 return '"' + this + '"';
};