1、QueryWrapper中in方法需要的格式是List
如果是这种类型直接放里就行例如:
List<String> typeList = new ArrayList<>();
queryWrapper.in("type",typeList)
2、如果传入的是1,2,3 这种格式需要解串生成List
String type = param.getType();
List<String> typeList = new ArrayList<>();
if(type != null) {
String[] typeStr = type .split(",");
for (int i = 0; i < typeStr.length; i++) {
typeList.add(typeStr[i]);
}
}
queryWrapper.in("type",typeList)
3、如果传递的是对象,需要通过遍历获取单个值,组成新的list
//查询到list集合
List<Type> typeList = typeService.selectById(id);
//结果集
List<String> typeList = new ArrayList<>();
//遍历集合取值
typeList.forEach(item->{
typeList.add(item.getType());
});
//条件构造器in上手使用
QueryWrapper<Type> queryWrapper = new QueryWrapper<>();
queryWrapper.in("type", typeList);