我正在使用 EF 5 构建 MVC 4 应用程序。 我需要进行审计跟踪，即记录最终用户所做的任何更改。

这个问题我已经问过几次了，但一直没有真正得到满意的答案。所以我添加了更多细节，希望能有所作为。

目前我有多个存储库

即

 public class AuditZoneRepository : IAuditZoneRepository
    {
        private AISDbContext context = new AISDbContext();


        public int Save(AuditZone model, ModelStateDictionary modelState)
        {
            if (model.Id == 0)
            {
                context.AuditZones.Add(model);
            }
            else
            {
                var recordToUpdate = context.AuditZones.FirstOrDefault(x => x.Id == model.Id);
                if (recordToUpdate != null)
                {
                    recordToUpdate.Description = model.Description;
                    recordToUpdate.Valid = model.Valid;
                    recordToUpdate.ModifiedDate = DateTime.Now;
                }
            }

            try
            {
                context.SaveChanges();
                return 1;
            }
            catch (Exception ex)
            {
                modelState.AddModelError("", "Database error has occured.  Please try again later");
                return -1;
            }
        }
    }



    public class PostcodesRepository : IPostcodesRepository
    {
        private AISDbContext context = new AISDbContext();


        public int Save(Postcodes model, ModelStateDictionary modelState)
        {
            if (model.Id == 0)
            {
                context.Postcodes.Add(model);
            }
            else
            {
                var recordToUpdate = context.Postcodes.FirstOrDefault(x => x.Id == model.Id);
                if (recordToUpdate != null)
                {
                    recordToUpdate.Suburb = model.Suburb;
                    recordToUpdate.State = model.State;
                    recordToUpdate.Postcode = model.Postcode;
                    recordToUpdate.AuditZoneId = model.AuditZoneId;
                    recordToUpdate.ModifiedDate = DateTime.Now;
                }
            }

            try
            {
                context.SaveChanges();
                return 1;
            }
            catch (Exception ex)
            {
                modelState.AddModelError("", "Database error has occured.  Please try again later");
                return -1;
            }
        }



    }

现在我知道要添加代码来检查是否有任何更改需要在尝试保存时添加。在 context.SaveChanges() 之前。

但目前我有 10 个 repo 协议(protocol)。我真的不想将代码添加到 10 个不同的地方。因为这段代码将做完全相同的事情。我想以某种方式拥有 repos 继承自的基类。

有什么帮助吗？任何示例代码？任何指针？

将不胜感激。我相信其他人以前会这样做

我正在像这样映射我的键、关系和表

 public class AuditZoneMap : EntityTypeConfiguration<AuditZone>
    {
        public AuditZoneMap()
        {
            // Primary Key
            HasKey(t => t.Id);


            // Properties
            Property(t => t.Description)
                .HasMaxLength(100);


            // Table & Column Mappings
            ToTable("AuditZone");
            Property(t => t.Id).HasColumnName("Id");
            Property(t => t.Description).HasColumnName("Description");
            Property(t => t.Valid).HasColumnName("Valid");          
            Property(t => t.CreatedDate).HasColumnName("CreatedDate");
            Property(t => t.CreatedBy).HasColumnName("CreatedBy");
            Property(t => t.ModifiedDate).HasColumnName("ModifiedDate");
            Property(t => t.ModifiedBy).HasColumnName("ModifiedBy");

            // Relationships        
            HasOptional(t => t.CreatedByUser)
               .WithMany(t => t.CreatedByAuditZone)
               .HasForeignKey(d => d.CreatedBy);

            HasOptional(t => t.ModifiedByUser)
                .WithMany(t => t.ModifiedByAuditZone)
                .HasForeignKey(d => d.ModifiedBy);


        }
    }

最佳答案

我建议您使用 EF 中的 ChangeTracker 属性。

在您的 DBContext.cs 中，您将拥有:

public class DBContext : DbContext
    {

        public DBContext () : base("DatabaseName")
        {

        }



        protected override void OnModelCreating(DbModelBuilder modelBuilder)
        {


        }

        public DbSet<YourPocoModelNameHere > YourPocoModelNameHere { get; set; }



        // This is overridden to prevent someone from calling SaveChanges without specifying the user making the change
        public override int SaveChanges()
        {
            throw new InvalidOperationException("User ID must be provided");
        }
        public int SaveChanges(int userId)
        {
            // Get all Added/Deleted/Modified entities (not Unmodified or Detached)
            foreach (var ent in this.ChangeTracker.Entries().Where(p => p.State == System.Data.EntityState.Added || p.State == System.Data.EntityState.Deleted || p.State == System.Data.EntityState.Modified))
            {
                // For each changed record, get the audit record entries and add them
                foreach (AuditLog x in GetAuditRecordsForChange(ent, userId))
                {
                    this.AuditLogs.Add(x);
                }
            }

            // Call the original SaveChanges(), which will save both the changes made and the audit records
            return base.SaveChanges();
        }

        private List<AuditLog> GetAuditRecordsForChange(DbEntityEntry dbEntry, int userId)
        {
            List<AuditLog> result = new List<AuditLog>();

            DateTime changeTime = DateTime.UtcNow;

            // Get the Table() attribute, if one exists
            //TableAttribute tableAttr = dbEntry.Entity.GetType().GetCustomAttributes(typeof(TableAttribute), false).SingleOrDefault() as TableAttribute;

            TableAttribute tableAttr = dbEntry.Entity.GetType().GetCustomAttributes(typeof(TableAttribute), true).SingleOrDefault() as TableAttribute;

            // Get table name (if it has a Table attribute, use that, otherwise get the pluralized name)
            string tableName = tableAttr != null ? tableAttr.Name : dbEntry.Entity.GetType().Name;

            // Get primary key value (If you have more than one key column, this will need to be adjusted)
            var keyNames = dbEntry.Entity.GetType().GetProperties().Where(p => p.GetCustomAttributes(typeof(KeyAttribute), false).Count() > 0).ToList();

            string keyName = keyNames[0].Name; //dbEntry.Entity.GetType().GetProperties().Single(p => p.GetCustomAttributes(typeof(KeyAttribute), false).Count() > 0).Name;

            if (dbEntry.State == System.Data.EntityState.Added)
            {
                // For Inserts, just add the whole record
                // If the entity implements IDescribableEntity, use the description from Describe(), otherwise use ToString()

                foreach (string propertyName in dbEntry.CurrentValues.PropertyNames)
                {
                    result.Add(new AuditLog()
                    {
                        AuditLogId = Guid.NewGuid(),
                        UserId = userId,
                        EventDateUTC = changeTime,
                        EventType = "A",    // Added
                        TableName = tableName,
                        RecordId = dbEntry.CurrentValues.GetValue<object>(keyName).ToString(),
                        ColumnName = propertyName,
                        NewValue = dbEntry.CurrentValues.GetValue<object>(propertyName) == null ? null : dbEntry.CurrentValues.GetValue<object>(propertyName).ToString()
                    }
                            );
                }
            }
            else if (dbEntry.State == System.Data.EntityState.Deleted)
            {
                // Same with deletes, do the whole record, and use either the description from Describe() or ToString()
                result.Add(new AuditLog()
                {
                    AuditLogId = Guid.NewGuid(),
                    UserId = userId,
                    EventDateUTC = changeTime,
                    EventType = "D", // Deleted
                    TableName = tableName,
                    RecordId = dbEntry.OriginalValues.GetValue<object>(keyName).ToString(),
                    ColumnName = "*ALL",
                    NewValue = (dbEntry.OriginalValues.ToObject() is IDescribableEntity) ? (dbEntry.OriginalValues.ToObject() as IDescribableEntity).Describe() : dbEntry.OriginalValues.ToObject().ToString()
                }
                    );
            }
            else if (dbEntry.State == System.Data.EntityState.Modified)
            {
                foreach (string propertyName in dbEntry.OriginalValues.PropertyNames)
                {
                    // For updates, we only want to capture the columns that actually changed
                    if (!object.Equals(dbEntry.OriginalValues.GetValue<object>(propertyName), dbEntry.CurrentValues.GetValue<object>(propertyName)))
                    {
                        result.Add(new AuditLog()
                        {
                            AuditLogId = Guid.NewGuid(),
                            UserId = userId,
                            EventDateUTC = changeTime,
                            EventType = "M",    // Modified
                            TableName = tableName,
                            RecordId = dbEntry.OriginalValues.GetValue<object>(keyName).ToString(),
                            ColumnName = propertyName,
                            OriginalValue = dbEntry.OriginalValues.GetValue<object>(propertyName) == null ? null : dbEntry.OriginalValues.GetValue<object>(propertyName).ToString(),
                            NewValue = dbEntry.CurrentValues.GetValue<object>(propertyName) == null ? null : dbEntry.CurrentValues.GetValue<object>(propertyName).ToString()
                        }
                            );
                    }
                }
            }
            // Otherwise, don't do anything, we don't care about Unchanged or Detached entities

            return result;
        }


    }

这将在您的数据库中使用下表:

USE [databasename]
GO

/****** Object:  Table [dbo].[auditlog]    Script Date: 06/01/2014 05:56:49 p. m. ******/
SET ANSI_NULLS ON
GO

SET QUOTED_IDENTIFIER ON
GO

SET ANSI_PADDING ON
GO

CREATE TABLE [dbo].[auditlog](
    [auditlogid] [uniqueidentifier] NOT NULL,
    [userid] [int] NOT NULL,
    [eventdateutc] [datetime] NOT NULL,
    [eventtype] [char](1) NOT NULL,
    [tablename] [nvarchar](100) NOT NULL,
    [recordid] [nvarchar](100) NOT NULL,
    [columnname] [nvarchar](100) NOT NULL,
    [originalvalue] [nvarchar](max) NULL,
    [newvalue] [nvarchar](max) NULL,
 CONSTRAINT [PK_AuditLog] PRIMARY KEY NONCLUSTERED 
(
    [auditlogid] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY] TEXTIMAGE_ON [PRIMARY]

GO

SET ANSI_PADDING OFF
GO

ALTER TABLE [dbo].[auditlog]  WITH CHECK ADD  CONSTRAINT [FK_auditlog_users] FOREIGN KEY([userid])
REFERENCES [dbo].[users] ([userid])
GO

ALTER TABLE [dbo].[auditlog] CHECK CONSTRAINT [FK_auditlog_users]
GO

一切就绪后，您只需调用 dbContext.SaveChanges(此处为 userId)；

希望这对你有用......我在我所有的应用程序中都使用它并且效果很好!

好好享受吧。

完整代码可在此处找到:https://jmdority.wordpress.com/2011/07/20/using-entity-framework-4-1-dbcontext-change-tracking-for-audit-logging/

关于c# - 如何使用 Entity Framework 5 和 MVC 4 创建审计跟踪，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/20961489/