目录

如何实现数据变更日志记录

前言

一、核心思想

二、实现步骤

1.在DbContext.cs文件中增加以下代码

2.增加AuditEntry.cs、DataOperationType.cs、IAuditConfig.cs、EFInternalExtensions.cs类

总结

protected List<AuditEntry>? AuditEntries { get; set; } = new List<AuditEntry>(); protected Task BeforeSaveChanges() { if (AuditConfig.AuditConfigOptions.AuditEnabled)
            { foreach (var entityEntry in ChangeTracker.Entries())
                { if (entityEntry.State == EntityState.Detached || entityEntry.State == EntityState.Unchanged)
                    { continue;
                    } // if (AuditConfig.AuditConfigOptions.EntityFilters.Any(entityFilter =>
                        entityFilter.Invoke(entityEntry) == false))
                    { continue;
                    }
                    AuditEntries.Add(new InternalAuditEntry(entityEntry));
                }
            } return Task.CompletedTask;
        } protected Task AfterSaveChanges() { if (null != AuditEntries && AuditEntries.Count > 0)
            { foreach (var entry in AuditEntries)
                { if (entry is InternalAuditEntry auditEntry)
                    { // update TemporaryProperties if (auditEntry.TemporaryProperties != null && auditEntry.TemporaryProperties.Count > 0)
                        { foreach (var temporaryProperty in auditEntry.TemporaryProperties)
                            { var colName = temporaryProperty.GetColumnName(); if (temporaryProperty.Metadata.IsPrimaryKey())
                                {
                                    auditEntry.KeyValues[colName] = temporaryProperty.CurrentValue;
                                } switch (auditEntry.OperationType)
                                { case DataOperationType.Add:
                                        auditEntry.NewValues![colName] = temporaryProperty.CurrentValue; break; case DataOperationType.Delete:
                                        auditEntry.OriginalValues![colName] = temporaryProperty.OriginalValue; break; case DataOperationType.Update:
                                        auditEntry.OriginalValues![colName] = temporaryProperty.OriginalValue;
                                        auditEntry.NewValues![colName] = temporaryProperty.CurrentValue; break;
                                }
                            } // set to null auditEntry.TemporaryProperties = null;
                        }
                    }



                }
            }

            AuditEntries.ForEach((e) => _logger.Info(JsonConvert.SerializeObject(e))); return Task.CompletedTask;
        } public override int SaveChanges() {
            BeforeSaveChanges().ConfigureAwait(false).GetAwaiter().GetResult(); var result = base.SaveChanges();
            AfterSaveChanges().ConfigureAwait(false).GetAwaiter().GetResult(); return result;
        } public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default) { await BeforeSaveChanges(); var result = await base.SaveChangesAsync(cancellationToken); await AfterSaveChanges(); return result;
        }

using Microsoft.EntityFrameworkCore; using Microsoft.EntityFrameworkCore.ChangeTracking; using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace RunGo.Admin.EntityFrameworkCore { public class AuditEntry { public string TableName { get; set; } = null!; public Dictionary<string, object?>? OriginalValues { get; set; } public Dictionary<string, object?>? NewValues { get; set; } public Dictionary<string, object?> KeyValues { get; } = new Dictionary<string, object?>(); public DataOperationType OperationType { get; set; } public Dictionary<string, object?> Properties { get; } = new Dictionary<string, object?>(); public DateTimeOffset UpdatedAt { get; set; } public string? UpdatedBy { get; set; }
    } internal sealed class InternalAuditEntry : AuditEntry { public List<PropertyEntry>? TemporaryProperties { get; set; } public InternalAuditEntry(EntityEntry entityEntry) {
            TableName = entityEntry.Metadata.GetTableName(); if (entityEntry.Properties.Any(x => x.IsTemporary))
            {
                TemporaryProperties = new List<PropertyEntry>(4);
            } if (entityEntry.State == EntityState.Added)
            {
                OperationType = DataOperationType.Add;
                NewValues = new Dictionary<string, object?>();
            } else if (entityEntry.State == EntityState.Deleted)
            {
                OperationType = DataOperationType.Delete;
                OriginalValues = new Dictionary<string, object?>();
            } else if (entityEntry.State == EntityState.Modified)
            {
                OperationType = DataOperationType.Update;
                OriginalValues = new Dictionary<string, object?>();
                NewValues = new Dictionary<string, object?>();
            } foreach (var propertyEntry in entityEntry.Properties)
            { if (AuditConfig.AuditConfigOptions.PropertyFilters.Any(f => f.Invoke(entityEntry, propertyEntry) == false))
                { continue;
                } if (propertyEntry.IsTemporary)
                {
                    TemporaryProperties!.Add(propertyEntry); continue;
                } var columnName = propertyEntry.GetColumnName(); if (propertyEntry.Metadata.IsPrimaryKey())
                {
                    KeyValues[columnName] = propertyEntry.CurrentValue;
                } switch (entityEntry.State)
                { case EntityState.Added:
                        NewValues![columnName] = propertyEntry.CurrentValue; break; case EntityState.Deleted:
                        OriginalValues![columnName] = propertyEntry.OriginalValue; break; case EntityState.Modified: if (propertyEntry.IsModified || AuditConfig.AuditConfigOptions.SaveUnModifiedProperties)
                        {
                            OriginalValues![columnName] = propertyEntry.OriginalValue;
                            NewValues![columnName] = propertyEntry.CurrentValue;
                        } break;
                }
            }
        }
    }
}

using System; using System.Collections.Generic; using System.Text; namespace RunGo.Admin.EntityFrameworkCore { public enum DataOperationType : sbyte { /// <summary> /// 查询 /// </summary> Query = 0, /// <summary> /// 新增 /// </summary> Add = 1, /// <summary> /// 删除 /// </summary> Delete = 2, /// <summary> /// 修改 /// </summary> Update = 3 }
}

using Microsoft.EntityFrameworkCore.ChangeTracking; using System; using System.Collections.Generic; using System.Text; namespace RunGo.Admin.EntityFrameworkCore { internal sealed class AuditConfigOptions { public bool AuditEnabled { get; set; } = true; public bool SaveUnModifiedProperties { get; set; } private IReadOnlyCollection<Func<EntityEntry, bool>> _entityFilters = Array.Empty<Func<EntityEntry, bool>>(); public IReadOnlyCollection<Func<EntityEntry, bool>> EntityFilters
        { get => _entityFilters; set => _entityFilters = value ?? throw new ArgumentNullException(nameof(value));
        } private IReadOnlyCollection<Func<EntityEntry, PropertyEntry, bool>> _propertyFilters = Array.Empty<Func<EntityEntry, PropertyEntry, bool>>(); public IReadOnlyCollection<Func<EntityEntry, PropertyEntry, bool>> PropertyFilters
        { get => _propertyFilters; set => _propertyFilters = value ?? throw new ArgumentNullException(nameof(value));
        }
       
    } public sealed class AuditConfig { internal static AuditConfigOptions AuditConfigOptions = new AuditConfigOptions(); public static void EnableAudit() {
            AuditConfigOptions.AuditEnabled = true;
        } public static void DisableAudit() {
            AuditConfigOptions.AuditEnabled = false;
        } #nullable disable #nullable restore }
}

using Microsoft.EntityFrameworkCore; using Microsoft.EntityFrameworkCore.ChangeTracking; using Microsoft.EntityFrameworkCore.Metadata; using System; using System.Collections.Generic; using System.Text; namespace RunGo.Admin.EntityFrameworkCore { public static class EFInternalExtensions { public static string GetColumnName(this PropertyEntry propertyEntry) { return propertyEntry.Metadata.Name;
        }
    }
}