使用LinqwebApiasp.net從多個表中洗掉行

public async Task<IHttpActionResult> DeleteUser(string id)
        {
            try {
                using (hospiceEntities db = new hospiceEntities())
                {
                    Guid guid_id = Guid.Parse(id);
                    var q =
                    (from user in db.Users
                     join resource in db.Resources
                     on user.Id equals resource.UserId
                     where user.Id == guid_id
                     select user).Single<User>();

                    foreach (Resource res in q.Resources)
                    {
                        db.Resources.Remove(res);

                    }
                    db.Users.Remove(q);
                    await db.SaveChangesAsync();
                    return Ok(Helper.SuccessResponse("User Deleted"));
                }
            }
            catch (Exception ex)
            {
                return BadRequest(ex.Message);
            }
        }

我有兩個通過外鍵約束連接的表用戶和資源。我已經撰寫了上面的 LINQ 查詢來洗掉記錄，但它沒有洗掉它。請告訴我我做錯了什么。謝謝

uj5u.com熱心網友回復：

嘗試使用此語法包含資源

    var user = await
    db.Users
   .Include(u=>u.Resources)
   .Where(u=> u.Id == guid_id)
   .FirstOrDefaltAsync();

   var res=user.Resources.ToList();
     db.Resources.RemoveRange(res);

    // or try directly
   db.Resources.RemoveRange(user.Resourses);

  //or maybe this is better
     user.Resources==null;
     
     db.Users.Remove(user);
     await db.SaveChangesAsync();
  

uj5u.com熱心網友回復：

在 foreach 回圈中使用它

(db.GetTable<Resource>().DeleteOnSubmit(res));

并使用此代碼

db.GetTable<Users>().DeleteOnSubmit(q);  
                    db.SubmitChanges();  

代替 (db.Users.Remove(q));

uj5u.com熱心網友回復：

以這種方式解決它：

 public async Task<IHttpActionResult> DeleteUser(string id)
        {
            try {
                using (hospiceEntities db = new hospiceEntities())
                {
                    Guid guid_id = Guid.Parse(id);
                    var deleteuser = db.Users.FirstOrDefault(e => e.Id == guid_id);
                    if (deleteuser == null)
                    {
                        return Content(HttpStatusCode.NotFound, "User Not Found");
                    }
                    else
                    {
                        var q =
                    from user in db.Users
                    join resource in db.Resources
                    on user.Id equals resource.UserId
                    where user.Id == guid_id
                    select new
                    {
                        Users = user,
                        Resources = resource
                    };
                        foreach (var item in q)
                        {
                            db.Resources.Remove(item.Resources);
                            db.Users.Remove(item.Users);
                        }
                        await db.SaveChangesAsync();
                    }
                }
                return Ok(Helper.SuccessResponse("User Deleted"));
            }
            catch (Exception ex)
            {
                return BadRequest(ex.Message);
            }
        }

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