How to convert special characters to HTML encoded equivalents using Javascript

function HTMLEncodeSpecialChars(strText)
{
  var sb = [];    
  for(var i = 0; i < strText.length; i++){
 var c = strText.substring(i,i+1); 
    if(c.charCodeAt()>127) // special chars
      sb.push('&#' +  c.charCodeAt() + ';');
    else
      sb.push(c);
  }
  
  return sb.join('');
}