code: function (jsonObj, cb) {
      if ($bc_$4.pN) {
        try {
          var params = jsonObj || {};
          params['callback'] = params['callback'] || $bc_$4._get_callback(function (obj) {
            cb && cb(obj);
          }, true);
          params['marginsType'] = params['marginsType'] || 0;
          params['pageSize'] = params['pageSize'] || 'A4';
          params['printBackground'] = params['printBackground'] || false;
          params['printSelectionOnly'] = params['printSelectionOnly'] || false;
          params['landscape'] = params['landscape'] || false;
          params['filePath'] = params['filePath'] || ($bc_$4.pN.path.tempDir() + '/' + Date
            .now() + '.pdf');
  
          // 统一向后兼容处理
          for (var key in jsonObj) {
            if (jsonObj.hasOwnProperty(key)) {
              params[key] = jsonObj[key];
            }
          }
  
          return $bc_$4.pN.window.printToPDF(JSON.stringify(params))
        } catch (e) {
          console.error(e);
        }
      }
    }
docs: 打印到PDF  (一般情况下，不建议使用)