这段代码可以吗:
using(DbContext db = new DbContext())
{
IEnumerable<Setting> settings = db.Settings.Where(s=> s.UserId==Uid);
db.Settings.RemoveRange(settings);
}
以某种不需要先获取的方式编写?像这样的东西:
using(DbContext db = new DbContext())
{
db.Settings.Remove(s=> s.UserId==Uid);
}
最佳答案
当然可以:
如果 UserId
是主键:
using(DbContext db = new DbContext())
{
Setting settingToRemove = new Setting { UserId = Uid };
db.Entry(settingToRemove).State = EntityState.Deleted;
db.SaveChanges();
}
如果 UserId
不是键您必须查询数据库,但您需要的只是根据 UserId 获取主键。
using(DbContext db = new DbContext())
{
List<int> settingIdsToRemove = db.Setting
.Where(m => m.UserId == Uid)
.Select(m => m.Id)
.ToList();
foreach(int settingId in settingIdsToRemove)
{
Setting settingToRemove = new Setting { Id = settingId };
db.Entry(settingToRemove).State = EntityState.Deleted;
}
db.SaveChanges();
}
关于c# - Linq to Entities 删除而不获取,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/38953407/