mybatis 查询

Posted 2020-10-29 zhoudingzhao

List<CustomerService> customerlist = customerService.selectByExample(customerexample); 
//如果在customer_service 表有用户的信息，则返回提示
System.out.println("cus:" + (null == customerlist));                      // 如果没有查出数据，customerlist 也不是 null， 可用 isEmpty() 函数判断，输出： cus:false
if (!customerlist.isEmpty()) {
return new JsonResult(false,"该手机号已经是客服号");
}