Get the before and after changes of navigation properties.

framework/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/EntityFrameworkCore/ChangeTrackers/AbpEfCoreNavigationHelper.cs

@@ -31,6 +31,14 @@ public class AbpEfCoreNavigationHelper : ITransientDependency
 
     protected virtual void EntityEntryTrackedOrStateChanged(EntityEntry entityEntry)
     {
+        if (entityEntry.State is EntityState.Unchanged or EntityState.Modified)
+        {
+            foreach (var entry in EntityEntries.Values.Where(x => x.NavigationEntries.Any()))
+            {
+                entry.UpdateNavigationEntries();
+            }
+        }
+
         if (entityEntry.State != EntityState.Unchanged)
         {
             return;
@@ -189,6 +197,22 @@ public class AbpEfCoreNavigationHelper : ITransientDependency
         return navigationEntryProperty != null && navigationEntryProperty.IsModified;
     }
 
+    public virtual AbpNavigationEntry? GetNavigationEntry(EntityEntry entityEntry, int navigationEntryIndex)
+    {
+        var entryId = GetEntityEntryIdentity(entityEntry);
+        if (entryId == null)
+        {
+            return null;
+        }
+
+        if (!EntityEntries.TryGetValue(entryId, out var abpEntityEntry))
+        {
+            return null;
+        }
+
+        return abpEntityEntry.NavigationEntries.ElementAtOrDefault(navigationEntryIndex);
+    }
+
     protected virtual string? GetEntityEntryIdentity(EntityEntry entityEntry)
     {
         if (entityEntry.Entity is IEntity entryEntity && entryEntity.GetKeys().Length == 1)

framework/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/EntityFrameworkCore/ChangeTrackers/AbpEntityEntry.cs

@@ -1,3 +1,4 @@
+using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
 using Microsoft.EntityFrameworkCore;
@@ -32,6 +33,49 @@ public class AbpEntityEntry
         EntityEntry = entityEntry;
         NavigationEntries = EntityEntry.Navigations.Select(x => new AbpNavigationEntry(x, x.Metadata.Name)).ToList();
     }
+
+    public void UpdateNavigationEntries()
+    {
+        foreach (var navigationEntry in NavigationEntries)
+        {
+            if (IsModified ||
+                EntityEntry.State == EntityState.Modified ||
+                navigationEntry.IsModified ||
+                navigationEntry.NavigationEntry.IsModified)
+            {
+                continue;
+            }
+
+            var navigation = EntityEntry.Navigations.FirstOrDefault(n => n.Metadata.Name == navigationEntry.Name);
+
+            var currentValue = AbpNavigationEntry.GetOriginalValue(navigation?.CurrentValue);
+            if (currentValue == null)
+            {
+                continue;
+            }
+
+            switch (navigationEntry.OriginalValue)
+            {
+                case null:
+                    navigationEntry.OriginalValue = currentValue;
+                    break;
+                case IEnumerable originalValueCollection when currentValue is IEnumerable currentValueCollection:
+                {
+                    var existingList = originalValueCollection.Cast<object?>().ToList();
+                    var newList = currentValueCollection.Cast<object?>().ToList();
+                    if (newList.Count > existingList.Count)
+                    {
+                        navigationEntry.OriginalValue = currentValue;
+                    }
+
+                    break;
+                }
+                default:
+                    navigationEntry.OriginalValue = currentValue;
+                    break;
+            }
+        }
+    }
 }
 
 public class AbpNavigationEntry
@@ -42,9 +86,29 @@ public class AbpNavigationEntry
 
     public bool IsModified { get; set; }
 
+    public List<object>? OriginalValue { get; set; }
+
+    public object? CurrentValue => NavigationEntry.CurrentValue;
+
     public AbpNavigationEntry(NavigationEntry navigationEntry, string name)
     {
         NavigationEntry = navigationEntry;
         Name = name;
+        OriginalValue = GetOriginalValue(navigationEntry.CurrentValue);
+    }
+
+    public static List<object>? GetOriginalValue(object? currentValue)
+    {
+        if (currentValue is null)
+        {
+            return null;
+        }
+
+        if (currentValue is IEnumerable enumerable)
+        {
+            return enumerable.Cast<object>().ToList();
+        }
+
+        return new List<object> { currentValue };
     }
 }

framework/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/EntityFrameworkCore/EntityHistory/EntityHistoryHelper.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Linq;
 using System.Reflection;
@@ -199,10 +200,14 @@ public class EntityHistoryHelper : IEntityHistoryHelper, ITransientDependency
             {
                 if (AbpEfCoreNavigationHelper.IsNavigationEntryModified(entityEntry, index))
                 {
+                    var abpNavigationEntry = AbpEfCoreNavigationHelper.GetNavigationEntry(entityEntry, index);
+                    var isCollection = navigationEntry.Metadata.IsCollection;
                     propertyChanges.Add(new EntityPropertyChangeInfo
                     {
                         PropertyName = navigationEntry.Metadata.Name,
-                        PropertyTypeFullName = navigationEntry.Metadata.ClrType.GetFirstGenericArgumentIfNullable().FullName!
+                        PropertyTypeFullName = navigationEntry.Metadata.ClrType.GetFirstGenericArgumentIfNullable().FullName!,
+                        OriginalValue = GetNavigationPropertyValue(abpNavigationEntry?.OriginalValue, isCollection),
+                        NewValue = GetNavigationPropertyValue(abpNavigationEntry?.CurrentValue, isCollection)
                     });
                 }
             }
@@ -211,6 +216,53 @@ public class EntityHistoryHelper : IEntityHistoryHelper, ITransientDependency
         return propertyChanges;
     }
 
+    protected virtual string? GetNavigationPropertyValue(object? entity, bool isCollection)
+    {
+        switch (entity)
+        {
+            case null:
+                return null;
+
+            case IEntity entryEntity:
+                var keys = entryEntity.GetKeys();
+                if (keys.Length == 0)
+                {
+                    return null;
+                }
+
+                var serializedKeys = keys.Length == 1 && !isCollection
+                    ? keys[0]?.ToString()
+                    : JsonSerializer.Serialize(keys);
+
+                return serializedKeys?.TruncateWithPostfix(EntityPropertyChangeInfo.MaxValueLength);
+
+            case IEnumerable enumerable:
+                var keysList = new List<string>();
+                foreach (var item in enumerable)
+                {
+                    var id = GetNavigationPropertyValue(item, false);
+                    if (id != null)
+                    {
+                        keysList.Add(id);
+                    }
+                }
+
+                if (keysList.Count == 0)
+                {
+                    return null;
+                }
+
+                var serializedKeysEnumerable = keysList.Count == 1 && !isCollection
+                    ? keysList.First()
+                    : JsonSerializer.Serialize(keysList);
+
+                return serializedKeysEnumerable.TruncateWithPostfix(EntityPropertyChangeInfo.MaxValueLength);
+
+            default:
+                return null;
+        }
+    }
+
     protected virtual bool IsCreated(EntityEntry entityEntry)
     {
         return entityEntry.State == EntityState.Added;

framework/test/Volo.Abp.Auditing.Tests/Volo/Abp/Auditing/Auditing_Tests.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using System.Text.Json;
 using System.Threading.Tasks;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
@@ -512,7 +513,9 @@ public class Auditing_Tests : AbpAuditingTestBase
                                                                      x.EntityChanges[1].EntityTypeFullName == typeof(AppEntityWithNavigations).FullName &&
                                                                      x.EntityChanges[1].PropertyChanges.Count == 1 &&
                                                                      x.EntityChanges[1].PropertyChanges[0].PropertyName == nameof(AppEntityWithNavigations.OneToOne) &&
-                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(AppEntityWithNavigationChildOneToOne).FullName));
+                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(AppEntityWithNavigationChildOneToOne).FullName &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].OriginalValue == null &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].NewValue == entityId.ToString()));
         AuditingStore.ClearReceivedCalls();
 #pragma warning restore 4014
 
@@ -539,10 +542,13 @@ public class Auditing_Tests : AbpAuditingTestBase
                                                                      x.EntityChanges[1].EntityTypeFullName == typeof(AppEntityWithNavigations).FullName &&
                                                                      x.EntityChanges[1].PropertyChanges.Count == 1 &&
                                                                      x.EntityChanges[1].PropertyChanges[0].PropertyName == nameof(AppEntityWithNavigations.OneToOne) &&
-                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(AppEntityWithNavigationChildOneToOne).FullName));
+                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(AppEntityWithNavigationChildOneToOne).FullName &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].OriginalValue == entityId.ToString() &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].NewValue == null));
         AuditingStore.ClearReceivedCalls();
 #pragma warning restore 4014
 
+        var oneToManyId = "";
         using (var scope = _auditingManager.BeginScope())
         {
             using (var uow = _unitOfWorkManager.Begin())
@@ -561,6 +567,8 @@ public class Auditing_Tests : AbpAuditingTestBase
                 await repository.UpdateAsync(entity);
                 await uow.CompleteAsync();
                 await scope.SaveAsync();
+
+                oneToManyId = entity.OneToMany.First().Id.ToString();
             }
         }
 
@@ -572,36 +580,80 @@ public class Auditing_Tests : AbpAuditingTestBase
                                                                      x.EntityChanges[1].EntityTypeFullName == typeof(AppEntityWithNavigations).FullName &&
                                                                      x.EntityChanges[1].PropertyChanges.Count == 1 &&
                                                                      x.EntityChanges[1].PropertyChanges[0].PropertyName == nameof(AppEntityWithNavigations.OneToMany) &&
-                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(List<AppEntityWithNavigationChildOneToMany>).FullName));
+                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(List<AppEntityWithNavigationChildOneToMany>).FullName &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].OriginalValue == null &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].NewValue == $"[\"{oneToManyId}\"]"));
         AuditingStore.ClearReceivedCalls();
 #pragma warning restore 4014
 
+        var newOneToManyId = "";
         using (var scope = _auditingManager.BeginScope())
         {
             using (var uow = _unitOfWorkManager.Begin())
             {
                 var entity = await repository.GetAsync(entityId);
 
-                entity.OneToMany = null;
+                entity.OneToMany.Add(new AppEntityWithNavigationChildOneToMany
+                {
+                    AppEntityWithNavigationId = entity.Id,
+                    ChildName = "ChildName2"
+                });
 
                 await repository.UpdateAsync(entity);
                 await uow.CompleteAsync();
                 await scope.SaveAsync();
+
+                newOneToManyId = JsonSerializer.Serialize(entity.OneToMany.Select(x => x.Id).ToList());
             }
         }
 
 #pragma warning disable 4014
         AuditingStore.Received().SaveAsync(Arg.Is<AuditLogInfo>(x => x.EntityChanges.Count == 2 &&
-                                                                     x.EntityChanges[0].ChangeType == EntityChangeType.Deleted &&
+                                                                     x.EntityChanges[0].ChangeType == EntityChangeType.Created &&
                                                                      x.EntityChanges[0].EntityTypeFullName == typeof(AppEntityWithNavigationChildOneToMany).FullName &&
                                                                      x.EntityChanges[1].ChangeType == EntityChangeType.Updated &&
                                                                      x.EntityChanges[1].EntityTypeFullName == typeof(AppEntityWithNavigations).FullName &&
                                                                      x.EntityChanges[1].PropertyChanges.Count == 1 &&
                                                                      x.EntityChanges[1].PropertyChanges[0].PropertyName == nameof(AppEntityWithNavigations.OneToMany) &&
-                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(List<AppEntityWithNavigationChildOneToMany>).FullName));
+                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(List<AppEntityWithNavigationChildOneToMany>).FullName &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].OriginalValue == $"[\"{oneToManyId}\"]" &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].NewValue == newOneToManyId));
+        AuditingStore.ClearReceivedCalls();
+#pragma warning restore 4014
+
+        using (var scope = _auditingManager.BeginScope())
+        {
+            using (var uow = _unitOfWorkManager.Begin())
+            {
+                var entity = await repository.GetAsync(entityId);
+
+                newOneToManyId = JsonSerializer.Serialize(entity.OneToMany.Select(x => x.Id).ToList());
+
+                entity.OneToMany = null;
+
+                await repository.UpdateAsync(entity);
+                await uow.CompleteAsync();
+                await scope.SaveAsync();
+            }
+        }
+
+#pragma warning disable 4014
+        AuditingStore.Received().SaveAsync(Arg.Is<AuditLogInfo>(x => x.EntityChanges.Count == 3 &&
+                                                                     x.EntityChanges[0].ChangeType == EntityChangeType.Deleted &&
+                                                                     x.EntityChanges[0].EntityTypeFullName == typeof(AppEntityWithNavigationChildOneToMany).FullName &&
+                                                                     x.EntityChanges[1].ChangeType == EntityChangeType.Deleted &&
+                                                                     x.EntityChanges[1].EntityTypeFullName == typeof(AppEntityWithNavigationChildOneToMany).FullName &&
+                                                                     x.EntityChanges[2].ChangeType == EntityChangeType.Updated &&
+                                                                     x.EntityChanges[2].EntityTypeFullName == typeof(AppEntityWithNavigations).FullName &&
+                                                                     x.EntityChanges[2].PropertyChanges.Count == 1 &&
+                                                                     x.EntityChanges[2].PropertyChanges[0].PropertyName == nameof(AppEntityWithNavigations.OneToMany) &&
+                                                                     x.EntityChanges[2].PropertyChanges[0].PropertyTypeFullName == typeof(List<AppEntityWithNavigationChildOneToMany>).FullName &&
+                                                                     x.EntityChanges[2].PropertyChanges[0].OriginalValue == newOneToManyId &&
+                                                                     x.EntityChanges[2].PropertyChanges[0].NewValue == null));
         AuditingStore.ClearReceivedCalls();
 #pragma warning restore 4014
 
+        var manyToManyId = "";
         using (var scope = _auditingManager.BeginScope())
         {
             using (var uow = _unitOfWorkManager.Begin())
@@ -619,6 +671,8 @@ public class Auditing_Tests : AbpAuditingTestBase
                 await repository.UpdateAsync(entity);
                 await uow.CompleteAsync();
                 await scope.SaveAsync();
+
+                manyToManyId = entity.ManyToMany.First().Id.ToString();
             }
         }
 
@@ -630,7 +684,9 @@ public class Auditing_Tests : AbpAuditingTestBase
                                                                      x.EntityChanges[1].EntityTypeFullName == typeof(AppEntityWithNavigations).FullName &&
                                                                      x.EntityChanges[1].PropertyChanges.Count == 1 &&
                                                                      x.EntityChanges[1].PropertyChanges[0].PropertyName == nameof(AppEntityWithNavigations.ManyToMany) &&
-                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(List<AppEntityWithNavigationChildManyToMany>).FullName));
+                                                                     x.EntityChanges[1].PropertyChanges[0].PropertyTypeFullName == typeof(List<AppEntityWithNavigationChildManyToMany>).FullName &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].OriginalValue == null &&
+                                                                     x.EntityChanges[1].PropertyChanges[0].NewValue == $"[\"{manyToManyId}\"]"));
 
 #pragma warning restore 4014
 
@@ -655,6 +711,8 @@ public class Auditing_Tests : AbpAuditingTestBase
                                                                      x.EntityChanges[0].PropertyChanges.Count == 1 &&
                                                                      x.EntityChanges[0].PropertyChanges[0].PropertyName == nameof(AppEntityWithNavigations.ManyToMany) &&
                                                                      x.EntityChanges[0].PropertyChanges[0].PropertyTypeFullName == typeof(List<AppEntityWithNavigationChildManyToMany>).FullName &&
+                                                                     x.EntityChanges[0].PropertyChanges[0].OriginalValue == $"[\"{manyToManyId}\"]" &&
+                                                                     x.EntityChanges[0].PropertyChanges[0].NewValue == null &&
 
                                                                      x.EntityChanges[1].ChangeType == EntityChangeType.Updated &&
                                                                      x.EntityChanges[1].EntityTypeFullName == typeof(AppEntityWithNavigationChildManyToMany).FullName &&