我的场景是根据多个id更新某个字段：

相当于sql语句：

update tb set name="zhangsan" where id in (1,2,3...)

①mapper.java文件和mapper.xml中分别添加代码：

int batchUpdateByPrimaryKey(Map map);

update systeminfo

set SystemLevelID = #{systemLevel,jdbcType=VARCHAR}

where SystemID in

#{params}

service中代码：

@Override

public CommonResult batchChangeSystemLevel(String systemInfos) {

JSONObject jsonObject = JSON.parseObject(systemInfos);

String systemIDs = jsonObject.getString("systemIDs");

String systemLevel = jsonObject.getString("systemLevel");

Map map = new HashMap<>();

map.put("systemLevel",systemLevel);

List systemIDList= Arrays.asList(systemIDs.split(","));

map.put("systemIDList",systemIDList);

systemInfoMapper.batchUpdateByPrimaryKey(map);

return CommonResult.ok();

}

controller中代码

public CommonResult batchChangeSystemLevel(@RequestBody String systemInfos) {

CommonResult result = systemInfoService.batchChangeSystemLevel(systemInfos);

return result;

}