我对EF内核还比较陌生,所以对我来说真是空子。
我正在尝试使用使用实体框架核心的数据库优先方法(因为代码首先也不起作用)创建应用程序。我已经成功地使用EF Core对所有模型进行了逆向工程,但是当尝试使用DbContext
向数据库中添加新项目时,我收到了一个视图嵌套异常消息。我的应用程序利用了两个多对多的关系。
我能够将单项添加到数据库中,将项目添加到联结表中会出现问题
该错误发生在
之后ctx.Usergorups.Add(newusergroup)
at
ctx.SaveChanges();
以及以下所有Add()
条语句:
Microsoft.EntityFrameworkCore.Infrastructure.IInfrastructure
.Instance'(((Microsoft.EntityFrameworkCore.Infrastructure.IInfrastructure )ctx.Usergroups).Instance'引发了类型为'System.NotImplementedException'的异常 System.IServiceProvider {System.NotImplementedException}
发生错误的地点:
private void Create_Group(object sender, RoutedEventArgs e)
{
string groupname = this.namebox.Text;
if (groupname.Equals("Enter user friendly name") || (groupname.Equals("")))
{
MessageBox.Show("The group name cannot be the default. Enter something something descriptive");
return;
}
else
{
try
{
List<UserUserGroup> usergroups = new List<UserUserGroup>();
List<AccessGroupUserGroup> Accessgroupers = new List<AccessGroupUserGroup>();
Usergroups newusergroup = new Usergroups()
{
Name = groupname
};
var ctx = new FMS_SIRContext();
ctx.Usergroups.Add(newusergroup);
ctx.SaveChanges();
foreach (Users u in this.members.Where(u => u != null))
{
usergroups.Add(new UserUserGroup()
{
UserId = u.Id,
User = u,
UserGroupId = newusergroup.Id,
UserGroup = newusergroup
});
}
ctx.UserUserGroup.AddRange(usergroups);
foreach (Accessgroups a in this.acceessGroups.Where(a => a != null))
{
Accessgroupers.Add(new AccessGroupUserGroup()
{
AccessGroup = a,
AccessGroupId = a.Id,
UserGroup = newusergroup,
UserGroupId = newusergroup.Id
});
}
ctx.AccessGroupUserGroup.AddRange(Accessgroupers);
ctx.SaveChanges();
this.Close();
}
catch (Exception s)
{
MessageBox.Show(s.Data.ToString());
}
}
}
我的DbContext
班:
public partial class FMS_SIRContext : DbContext
{
public FMS_SIRContext()
{
}
public FMS_SIRContext(DbContextOptions<FMS_SIRContext> options)
: base(options)
{
this.ChangeTracker.LazyLoadingEnabled = false;
}
public virtual DbSet<AccessGroupUserGroup> AccessGroupUserGroup { get; set; }
public virtual DbSet<Accessgroups> Accessgroups { get; set; }
public virtual DbSet<UserUserGroup> UserUserGroup { get; set; }
public virtual DbSet<Usergroups> Usergroups { get; set; }
public virtual DbSet<Users> Users { get; set; }
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
if (!optionsBuilder.IsConfigured)
{
optionsBuilder.UseSqlServer("Data Source=az18w7413;Initial Catalog=****;Persist Security Info=True;User ID=******;Password=******;");
}
}
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<AccessGroupUserGroup>(entity =>
{
entity.HasKey(e => new { e.AccessGroupId, e.UserGroupId });
entity.ToTable("AccessGroupUserGroup", "asps");
entity.HasIndex(e => e.UserGroupId);
entity.Property(e => e.AccessGroupId).HasColumnName("AccessGroupID");
entity.Property(e => e.UserGroupId).HasColumnName("UserGroupID");
entity.HasOne(d => d.AccessGroup)
.WithMany(p => p.AccessGroupUserGroup)
.HasForeignKey(d => d.AccessGroupId);
entity.HasOne(d => d.UserGroup)
.WithMany(p => p.AccessGroupUserGroup)
.HasForeignKey(d => d.UserGroupId);
});
modelBuilder.Entity<Accessgroups>(entity =>
{
entity.ToTable("accessgroups", "asps");
entity.Property(e => e.Id).HasColumnName("ID");
entity.Property(e => e.Itname).HasColumnName("ITNAME");
entity.Property(e => e.Name).HasColumnName("NAME");
entity.Property(e => e.Permission).HasColumnName("PERMISSION");
});
modelBuilder.Entity<UserUserGroup>(entity =>
{
entity.HasKey(e => new { e.UserId, e.UserGroupId });
entity.ToTable("UserUserGroup", "asps");
entity.HasIndex(e => e.UserGroupId);
entity.Property(e => e.UserId).HasColumnName("UserID");
entity.Property(e => e.UserGroupId).HasColumnName("UserGroupID");
entity.HasOne(d => d.UserGroup)
.WithMany(p => p.UserUserGroup)
.HasForeignKey(d => d.UserGroupId);
entity.HasOne(d => d.User)
.WithMany(p => p.UserUserGroup)
.HasForeignKey(d => d.UserId)
.OnDelete(DeleteBehavior.ClientSetNull)
.HasConstraintName("FK_UserUserGroup_User");
});
modelBuilder.Entity<Usergroups>(entity =>
{
entity.ToTable("usergroups", "asps");
entity.Property(e => e.Id).HasColumnName("ID");
entity.Property(e => e.Name).HasColumnName("NAME");
});
modelBuilder.Entity<Users>(entity =>
{
entity.ToTable("Users", "asps");
entity.HasIndex(e => e.Eid)
.HasName("IX_EID")
.IsUnique();
entity.HasIndex(e => e.Id)
.HasName("IX_ID");
entity.Property(e => e.Id).HasColumnName("ID");
entity.Property(e => e.Eid)
.HasColumnName("EID")
.HasMaxLength(50);
entity.Property(e => e.FirstName).HasMaxLength(100);
entity.Property(e => e.LastName).HasMaxLength(100);
entity.Property(e => e.LocationId).HasColumnName("LocationID");
entity.Property(e => e.Mail).HasMaxLength(200);
});
OnModelCreatingPartial(modelBuilder);
}
partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
}
答案 0 :(得分:1)
我终于知道了(8小时后)。这不是依赖性注入问题,而是ID分配错误。我分配了用户,用户组,访问组和用户组的ID并分配了对象,因此使默认构造函数的ID为0。
private void Create_Group(object sender, RoutedEventArgs e)
{
string groupname = this.namebox.Text;
if (groupname.Equals("Enter user friendly name") || (groupname.Equals("")))
{
MessageBox.Show("The group name cannot be the default. Enter something something descriptive");
return;
}
else
{
try
{
List<UserUserGroup> usergroups = new List<UserUserGroup>();
List<AccessGroupUserGroup> Accessgroupers = new List<AccessGroupUserGroup>();
Usergroups newusergroup = new Usergroups()
{
Name = groupname
};
FMS_SIRContext ctx = new FMS_SIRContext();
ctx.Usergroups.Add(newusergroup);
ctx.SaveChanges();
foreach (Users u in members.Where(u => u != null))
{
usergroups.Add(new UserUserGroup()
{
UserId = u.Id,
//User = u,
UserGroupId = newusergroup.Id,
//UserGroup = newusergroup
});
}
//ctx.Usergroups.Add(newusergroup);
ctx.AddRange(usergroups);
foreach (Accessgroups a in this.acceessGroups.Where(a => a != null))
{
Accessgroupers.Add(new AccessGroupUserGroup()
{
//AccessGroup = a,
AccessGroupId = a.Id,
//UserGroup = newusergroup,
UserGroupId = newusergroup.Id
});
}
ctx.AddRange(Accessgroupers);
ctx.SaveChanges();
this.Close();
}
catch (Exception s)
{
MessageBox.Show(s.Data.ToString());
}
}
}