我们正在尝试简化 DateCreated，CreatedBy，LastDateModified，LastModifiedBy，DateDeleted和DeletedBy 的自动更新字段，并通过在ApplicationDBContext.cs中添加例程OnBeforeSaving使其正常工作，并且我们也执行了 SOFT-DELETE 用于在我们删除时保留记录（改为标记为IsDeleted）：
ApplicationDBContext.cs -
using System;
using System.Collections.Generic;
using System.Text;
using Microsoft.AspNetCore.Identity.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore;
using AthlosifyWebArchery.Models;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using System.Linq.Expressions;
using Microsoft.AspNetCore.Http;
using System.Security.Claims;
using Microsoft.AspNetCore.Identity;
namespace AthlosifyWebArchery.Data
{
public class ApplicationDbContext : IdentityDbContext<ApplicationUser, ApplicationRole, string,
IdentityUserClaim<string>,
ApplicationUserRole, IdentityUserLogin<string>,
IdentityRoleClaim<string>, IdentityUserToken<string>>
{
private readonly IHttpContextAccessor _httpContextAccessor;
public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options,
IHttpContextAccessor httpContextAccessor
)
: base(options)
{
_httpContextAccessor = httpContextAccessor;
}
public DbSet<AthlosifyWebArchery.Models.TournamentBatchItem> TournamentBatchItem { get; set; }
public DbSet<AthlosifyWebArchery.Models.TournamentBatch> TournamentBatch { get; set; }
public virtual DbSet<AthlosifyWebArchery.Models.Host> Host { get; set; }
public DbSet<AthlosifyWebArchery.Models.HostApplicationUser> HostApplicationUser { get; set; }
public virtual DbSet<AthlosifyWebArchery.Models.Club> Club { get; set; }
public DbSet<AthlosifyWebArchery.Models.ClubApplicationUser> ClubApplicationUser { get; set; }
protected override void OnModelCreating(ModelBuilder builder)
{
base.OnModelCreating(builder);
foreach (var entityType in builder.Model.GetEntityTypes())
{
// 1. Add the IsDeleted property
entityType.GetOrAddProperty("IsDeleted", typeof(bool));
// 2. Create the query filter
var parameter = Expression.Parameter(entityType.ClrType);
// EF.Property<bool>(post, "IsDeleted")
var propertyMethodInfo = typeof(EF).GetMethod("Property").MakeGenericMethod(typeof(bool));
var isDeletedProperty = Expression.Call(propertyMethodInfo, parameter, Expression.Constant("IsDeleted"));
// EF.Property<bool>(post, "IsDeleted") == false
BinaryExpression compareExpression = Expression.MakeBinary(ExpressionType.Equal, isDeletedProperty, Expression.Constant(false));
// post => EF.Property<bool>(post, "IsDeleted") == false
var lambda = Expression.Lambda(compareExpression, parameter);
builder.Entity(entityType.ClrType).HasQueryFilter(lambda);
}
// Many to Many relationship - HostApplicationUser
builder.Entity<HostApplicationUser>()
.HasKey(bc => new { bc.HostID, bc.Id });
builder.Entity<HostApplicationUser>()
.HasOne(bc => bc.Host)
.WithMany(b => b.HostApplicationUsers)
.HasForeignKey(bc => bc.HostID);
builder.Entity<HostApplicationUser>()
.HasOne(bc => bc.ApplicationUser)
.WithMany(c => c.HostApplicationUsers)
.HasForeignKey(bc => bc.Id);
// Many to Many relationship - ClubApplicationUser
builder.Entity<ClubApplicationUser>()
.HasKey(bc => new { bc.ClubID, bc.Id });
builder.Entity<ClubApplicationUser>()
.HasOne(bc => bc.Club)
.WithMany(b => b.ClubApplicationUsers)
.HasForeignKey(bc => bc.ClubID);
builder.Entity<ClubApplicationUser>()
.HasOne(bc => bc.ApplicationUser)
.WithMany(c => c.ClubApplicationUsers)
.HasForeignKey(bc => bc.Id);
// Many to Many relationship - ApplicationUserRole
builder.Entity<ApplicationUserRole>(userRole =>
{
userRole.HasKey(ur => new { ur.UserId, ur.RoleId });
userRole.HasOne(ur => ur.Role)
.WithMany(r => r.UserRoles)
.HasForeignKey(ur => ur.RoleId)
.IsRequired();
userRole.HasOne(ur => ur.User)
.WithMany(r => r.ApplicationUserRoles)
.HasForeignKey(ur => ur.UserId)
.IsRequired();
});
}
public override int SaveChanges(bool acceptAllChangesOnSuccess)
{
OnBeforeSaving();
return base.SaveChanges(acceptAllChangesOnSuccess);
}
public override Task<int> SaveChangesAsync(bool acceptAllChangesOnSuccess, CancellationToken cancellationToken = default(CancellationToken))
{
OnBeforeSaving();
return base.SaveChangesAsync(acceptAllChangesOnSuccess, cancellationToken);
}
private void OnBeforeSaving()
{
if (_httpContextAccessor.HttpContext != null)
{
var userName = _httpContextAccessor.HttpContext.User.Identity.Name;
var userId = _httpContextAccessor.HttpContext.User.FindFirstValue(ClaimTypes.NameIdentifier);
// Added
var added = ChangeTracker.Entries().Where(v => v.State == EntityState.Added &&
typeof(IBaseEntity).IsAssignableFrom(v.Entity.GetType())).ToList();
added.ForEach(entry =>
{
((IBaseEntity)entry.Entity).DateCreated = DateTime.UtcNow;
((IBaseEntity)entry.Entity).CreatedBy = userId;
((IBaseEntity)entry.Entity).LastDateModified = DateTime.UtcNow;
((IBaseEntity)entry.Entity).LastModifiedBy = userId;
});
// Modified
var modified = ChangeTracker.Entries().Where(v => v.State == EntityState.Modified &&
typeof(IBaseEntity).IsAssignableFrom(v.Entity.GetType())).ToList();
modified.ForEach(entry =>
{
((IBaseEntity)entry.Entity).LastDateModified = DateTime.UtcNow;
((IBaseEntity)entry.Entity).LastModifiedBy = userId;
});
// Deleted
var deleted = ChangeTracker.Entries().Where(v => v.State == EntityState.Deleted &&
typeof(IBaseEntity).IsAssignableFrom(v.Entity.GetType())).ToList();
deleted.ForEach(entry =>
{
((IBaseEntity)entry.Entity).DateDeleted = DateTime.UtcNow;
((IBaseEntity)entry.Entity).DeletedBy = userId;
});
foreach (var entry in ChangeTracker.Entries()
.Where(e => e.State == EntityState.Deleted &&
e.Metadata.GetProperties().Any(x => x.Name == "IsDeleted")))
{
switch (entry.State)
{
case EntityState.Added:
entry.CurrentValues["IsDeleted"] = false;
break;
case EntityState.Deleted:
entry.State = EntityState.Modified;
entry.CurrentValues["IsDeleted"] = true;
break;
}
}
}
else
{
// DbInitializer kicks in
}
}
}
}
在独立模型/类中可以正常工作，即。 俱乐部，主机，ApplicationUser **但不桥接模型/类，即** ClubApplicationUser和HostApplicationUser
因此，我们必须为此手动进行操作（例如，AssignClub.cshtml.cs），方法是手动添加以创建/删除操作，如下所示：
// Removed the current one
var clubApplicationUserToRemove = await _context.ClubApplicationUser
.FirstOrDefaultAsync(m => m.Id == id.ToString()
&& m.ClubID == AssignClubUser.OriginalClubID);
clubApplicationUserToRemove.DateDeleted = DateTime.UtcNow;
clubApplicationUserToRemove.DeletedBy = userID;
_context.ClubApplicationUser.Remove(clubApplicationUserToRemove);
...下面的 deleted.Count（）返回0 ...，与创建etc相同：
// Deleted
var deleted = ChangeTracker.Entries().Where(v => v.State == EntityState.Deleted &&
typeof(IBaseEntity).IsAssignableFrom(v.Entity.GetType())).ToList();
deleted.ForEach(entry =>
{
((IBaseEntity)entry.Entity).DateDeleted = DateTime.UtcNow;
((IBaseEntity)entry.Entity).DeletedBy = userId;
});
AssignClub.cshtml.cs -
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;
using Microsoft.AspNetCore.Mvc.Rendering;
using Microsoft.EntityFrameworkCore;
using AthlosifyWebArchery.Data;
using AthlosifyWebArchery.Models;
using AthlosifyWebArchery.Pages.Administrators.TournamentBatches;
using Microsoft.AspNetCore.Identity;
using System.ComponentModel.DataAnnotations;
using static AthlosifyWebArchery.Pages.Administrators.Users.AssignClubUserModel;
using Microsoft.AspNetCore.Http;
using System.Security.Claims;
namespace AthlosifyWebArchery.Pages.Administrators.Users
{
//public class AssignClubUserModel : ClubNamePageModel
public class AssignClubUserModel : UserViewPageModel
{
private readonly AthlosifyWebArchery.Data.ApplicationDbContext _context;
private readonly IHttpContextAccessor _httpContextAccessor;
public AssignClubUserModel(AthlosifyWebArchery.Data.ApplicationDbContext context,
IHttpContextAccessor httpContextAccessor
)
{
_context = context;
_httpContextAccessor = httpContextAccessor;
}
public class AssignClubUserViewModel<ApplicationUser>
{
public string Id { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public string UserName { get; set; }
public Guid ClubID { get; set; }
public Guid OriginalClubID { get; set; }
public byte[] RowVersion { get; set; }
}
[BindProperty]
public AssignClubUserViewModel<ApplicationUser> AssignClubUser { get; set; }
//public SelectList ClubNameSL { get; set; }
public async Task<IActionResult> OnGetAsync(Guid? id)
{
if (id == null)
return NotFound();
AssignClubUser = await _context.Users
.Include(u => u.ClubApplicationUsers)
.Where(t => t.Id == id.ToString())
.Select(t => new AssignClubUserViewModel<ApplicationUser>
{
Id = t.Id,
FirstName = t.FirstName,
LastName = t.LastName,
UserName = t.UserName,
ClubID = t.ClubApplicationUsers.ElementAt(0).ClubID,
OriginalClubID = t.ClubApplicationUsers.ElementAt(0).ClubID,
RowVersion = t.ClubApplicationUsers.ElementAt(0).RowVersion
}).SingleAsync();
if (AssignClubUser == null)
return NotFound();
// Use strongly typed data rather than ViewData.
//ClubNameSL = new SelectList(_context.Club, "ClubID", "Name");
PopulateClubsDropDownList(_context, AssignClubUser.ClubID);
return Page();
}
public async Task<IActionResult> OnPostAsync(Guid id)
{
if (!ModelState.IsValid)
return Page();
// 1st approach:
// Modify the bridge model directly
/*var clubApplicationUserToUpdate = await _context.ClubApplicationUser
.FirstOrDefaultAsync(m => m.Id == id.ToString()
&& m.ClubID == AssignClubUser.OriginalClubID);
if (clubApplicationUserToUpdate == null)
return await HandleDeletedUser();
_context.Entry(clubApplicationUserToUpdate)
.Property("RowVersion").OriginalValue = AssignClubUser.RowVersion;
// This slightly tweek for this particular
// As the modified Change Track is not triggered
//_context.Entry(clubApplicationUserToUpdate)
// .Property("LastDateModified").CurrentValue = DateTime.UtcNow;
//_context.Entry(clubApplicationUserToUpdate)
// .Property("LastModifiedBy").CurrentValue = _httpContextAccessor.HttpContext.User.FindFirstValue(ClaimTypes.NameIdentifier);
if (await TryUpdateModelAsync<ClubApplicationUser>(
clubApplicationUserToUpdate,
"AssignClubUser",
s => s.Id, s => s.ClubID))
{
try
{
await _context.SaveChangesAsync();
return RedirectToPage("./Index");
}
catch (DbUpdateConcurrencyException ex)
{
var exceptionEntry = ex.Entries.Single();
var clientValues = (ClubApplicationUser)exceptionEntry.Entity;
var databaseEntry = exceptionEntry.GetDatabaseValues();
if (databaseEntry == null)
{
ModelState.AddModelError(string.Empty, "Unable to save. " +
"The club application user was deleted by another user.");
return Page();
}
var dbValues = (ClubApplicationUser)databaseEntry.ToObject();
await setDbErrorMessage(dbValues, clientValues, _context);
AssignClubUser.RowVersion = (byte[])dbValues.RowVersion;
ModelState.Remove("User.RowVersion");
}
}
*/
// 2nd approach:
// Soft -Delete and Add
// Did the soft-deleting and managed to add a new one BUT then die the roll back (adding the old one)
// Result: Violation of PRIMARY KEY constraint 'PK_ClubApplicationUser'.
// Cannot insert duplicate key in object
// Due to duplicate key
/*var clubApplicatonUserToRemove = await _context.ClubApplicationUser
.FirstOrDefaultAsync(m => m.Id == id.ToString());
ClubApplicationUser clubApplicatonUserToAdd = new ClubApplicationUser();
clubApplicatonUserToAdd.Id = id.ToString();
clubApplicatonUserToAdd.ClubID = AssignClubUser.SelectedClubID;
//_context.Entry(clubApplicatonUserToRemove)
// .Property("RowVersion").OriginalValue = User.RowVersion;
if (clubApplicatonUserToRemove != null)
{
_context.ClubApplicationUser.Remove(clubApplicatonUserToRemove);
await _context.SaveChangesAsync();clubApplicationUserDeleted
_context.ClubApplicationUser.Add(clubApplicatonUserToAdd);
await _context.SaveChangesAsync();
}*/
//delete all club memberships and add new one
//var clubApplicationUserDeleted = await _context.ClubApplicationUser
// .FirstOrDefaultAsync(m => m.Id == id.ToString()
// && m.ClubID == AssignClubUser.ClubID && m.IsDeleted == );
var userID = _httpContextAccessor.HttpContext.User.FindFirstValue(ClaimTypes.NameIdentifier);
if (AssignClubUser.ClubID != AssignClubUser.OriginalClubID)
{
var deletedClubApplicationUsers = _context.ClubApplicationUser.IgnoreQueryFilters()
.Where(post => post.Id == id.ToString()
&& post.ClubID == AssignClubUser.ClubID && EF.Property<bool>(post, "IsDeleted") == true);
if (deletedClubApplicationUsers.Count() > 0)
{
// Undo the deleted one
foreach (var deletedClubApplicationUser in deletedClubApplicationUsers)
{
var postEntry = _context.ChangeTracker.Entries<ClubApplicationUser>().First(entry => entry.Entity == deletedClubApplicationUser);
postEntry.Property("IsDeleted").CurrentValue = false;
postEntry.Property("LastDateModified").CurrentValue = DateTime.UtcNow;
postEntry.Property("LastModifiedBy").CurrentValue = userID;
postEntry.Property("DateDeleted").CurrentValue = null;
postEntry.Property("DeletedBy").CurrentValue = null;
}
// Removed the current one
var clubApplicationUserToRemove = await _context.ClubApplicationUser
.FirstOrDefaultAsync(m => m.Id == id.ToString()
&& m.ClubID == AssignClubUser.OriginalClubID);
clubApplicationUserToRemove.DateDeleted = DateTime.UtcNow;
clubApplicationUserToRemove.DeletedBy = userID;
_context.ClubApplicationUser.Remove(clubApplicationUserToRemove);
try
{
await _context.SaveChangesAsync();
return RedirectToPage("./Index");
}
catch
{
PopulateClubsDropDownList(_context, AssignClubUser.ClubID);
return Page();
}
}
else
{
// Removed the current one
var clubApplicationUserToRemove = await _context.ClubApplicationUser
.FirstOrDefaultAsync(m => m.Id == id.ToString()
&& m.ClubID == AssignClubUser.OriginalClubID);
clubApplicationUserToRemove.DateDeleted = DateTime.UtcNow;
clubApplicationUserToRemove.DeletedBy = userID;
_context.ClubApplicationUser.Remove(clubApplicationUserToRemove);
try
{
_context.Entry(clubApplicationUserToRemove).State = EntityState.Deleted;
await _context.SaveChangesAsync();
}
catch
{
PopulateClubsDropDownList(_context, AssignClubUser.ClubID);
return Page();
}
// Added the new one
var newClubApplicationUser = new ClubApplicationUser()
{
Id = id.ToString(),
ClubID = AssignClubUser.ClubID,
DateCreated = DateTime.UtcNow,
CreatedBy = userID,
LastDateModified = DateTime.UtcNow,
LastModifiedBy = userID
};
_context.ClubApplicationUser.Add(newClubApplicationUser);
try
{
_context.Entry(newClubApplicationUser).State = EntityState.Added;
await _context.SaveChangesAsync();
return RedirectToPage("./Index");
}
catch
{
PopulateClubsDropDownList(_context, AssignClubUser.ClubID);
return Page();
}
}
}
return RedirectToPage("./Index");
}
private async Task<IActionResult> HandleDeletedUser()
{
ClubApplicationUser deletedClubApplicationUser = new ClubApplicationUser();
ModelState.AddModelError(string.Empty,
"Unable to save. The club was deleted by another user.");
return Page();
}
private async Task setDbErrorMessage(ClubApplicationUser dbValues,
ClubApplicationUser clientValues, ApplicationDbContext context)
{
ModelState.AddModelError(string.Empty,
"The record you attempted to edit "
+ "was modified by another user after you. The "
+ "edit operation was canceled and the current values in the database "
+ "have been displayed. If you still want to edit this record, click "
+ "the Save button again.");
}
}
}
ClubApplicationUser.cs模型：
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;
using System.Linq;
using System.Threading.Tasks;
namespace AthlosifyWebArchery.Models
{
public class ClubApplicationUser
{
public Guid ClubID { get; set; }
public Club Club { get; set; }
public string Id { get; set; }
public ApplicationUser ApplicationUser { get; set; }
public DateTime DateCreated { get; set; }
public string CreatedBy { get; set; }
public DateTime LastDateModified { get; set; }
public string LastModifiedBy { get; set; }
public DateTime? DateDeleted { get; set; }
public string DeletedBy { get; set; }
public bool IsDeleted { get; set; }
[Timestamp]
public byte[] RowVersion { get; set; }
[ForeignKey("CreatedBy")]
public ApplicationUser ClubApplicationCreatedUser { get; set; }
[ForeignKey("LastModifiedBy")]
public ApplicationUser ClubApplicationLastModifiedUser { get; set; }
}
}
有什么想法吗？当前的解决方案可以正常工作，但是它只有额外的例程可以为此桥接模型/类手动添加这些DateCreated，CreatedBy，LastDateModified，LastModifiedBy，DateDeleted和DeletedBy。
环境：
更新1：
我们甚至在保存之前添加了它，它并没有触发自动 ChangeTracker.Entries（）：
_context.Entry(newClubApplicationUser).State = EntityState.Deleted;
await _context.SaveChangesAsync();
更新2：
在上面添加了ClubApplicationUser模型。