[英]EF7 nested Include not showing in Razor .net
我有這樣的模型:
現在,當用戶屬於該組時,我想在詳細信息頁面上的“個人資料”中顯示數據。 我這樣做是這樣的:
private IEnumerable<GroupUser> GetUsers(int groupId)
{
IEnumerable<GroupUser> model = null;
if(groupId == 0)
{
model = _kletsContext.GroupUser.OrderByDescending(o => o.GroupId).AsEnumerable();
}
else
{
model = _kletsContext.GroupUser.Where(g => g.GroupId == groupId).Include(p => p.User.Profile).OrderByDescending(o => o.GroupId).AsEnumerable();
}
return model;
}
如果我只想使用以下代碼顯示UserId,...(即數據透視表中的數據),則此方法有效:
@model IEnumerable<App.Models.GroupUser>
@if(Model != null && Model.Count() > 0)
{
@foreach(var user in Model)
{
@user.UserId</h2>
}
}
但是由於某種原因,我無法在“包含”表中顯示數據? 通常,您會執行以下操作:@ user.User.Profile.XXXX,但隨后出現錯誤: System.NullReferenceException: Object reference not set to an instance of an object
因此這意味着返回值為null,但是有用戶在帶有配置文件的數據透視表中。
型號:
Group.cs:
namespace App.Models
{
public class Group : Item
{
public Group() : base()
{
}
[Key]
public Int16 Id { get; set; }
public string Name { get; set; }
public string Images { get; set; }
/* Foreign Keys */
public Nullable<Int16> RegionId { get; set; }
public virtual Region Region { get; set; }
public virtual ICollection<Lets> Lets { get; set; }
public virtual ICollection<GroupUser> Users { get; set; }
}
}
應用用戶:
namespace App.Models.Identity
{
public class ApplicationUser : IdentityUser
{
public string Description { get; set; }
public DateTime CreatedAt { get; set; }
public Nullable<DateTime> UpdatedAt { get; set; }
public Nullable<DateTime> DeletedAt { get; set; }
/* Virtual or Navigation Properties */
public virtual Profile Profile { get; set; }
public virtual ICollection<GroupUser> Groups { get; set; }
public virtual ICollection<Lets> Lets { get; set; }
public virtual ICollection<Category> Categories { get; set; }
public virtual ICollection<Region> Regions { get; set; }
public virtual ICollection<Status> Status { get; set; }
public virtual ICollection<Tag> Tags { get; set; }
}
}
GroupUser:
namespace App.Models
{
public class GroupUser
{
public GroupUser()
{
}
public Nullable<Int16> GroupId { get; set; }
public string UserId { get; set; }
public virtual Group Group { get; set; }
public virtual ApplicationUser User { get; set; }
}
}
Profile.cs:
namespace App.Models
{
public class Profile : Item
{
public Profile() : base()
{
}
[Key]
public string UserId { get; set; }
public string FirstName { get; set; }
public string SurName { get; set; }
public string Email { get; set; }
public string Gender { get; set; }
public Int16 Age { get; set; }
public string City { get; set; }
public string Image { get; set; }
public Int16 Credits { get; set; }
public Int16 Postalcode { get; set; }
}
}
如何使用剃須刀顯示嵌套數據?
model = _kletsContext.GroupUser.Where(g => g.GroupId == groupId)
.Include(gu => gu.User)
.ThenInclude(u => u.Profile)
.OrderByDescending(o => o.GroupId)
.AsEnumerable();
當intellisense對於ThenInclude
,請不要ThenInclude
,只需鍵入它,它將進行編譯。
嘗試包括用戶參考
模型= _kletsContext.GroupUser.Where(g => g.GroupId == groupId) .Include(p => p.User) .Include(p => p.User.Profile).OrderByDescending(o => o.GroupId) .AsEnumerable();
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