function toTxt(str) {    var RexStr = //<|/>|/"|/'|/&/g    str = str.replace(RexStr, function(MatchStr) {      switch (MatchStr) {      case "<":        return "<";        break;      case ">":        return ">";        break;      case "/"":        return """;        break;      case "'":        return "'";        break;      case "&":        return "&";        break;      default:        break;      }    })    return str;  }