我正在尝试使用 EF DbContext 为我的系统执行审核方法。我覆盖了"保存更改"事件。但是，我有两个困难需要帮助。我在互联网上和StackOverflow上读了很多书，但我仍然无法找到解决方案。你可以帮我吗？
1） 添加记录时无法获取表的实际名称。当我将记录添加到表中时，只需出现名称"对象"。其他具有该名称的操作通常。
2） 进入注册表后，我希望将注册表 ID 放入审核日志中。有什么建议吗？
如果问题如此明显，我期待道歉，但我真的不明白如何进行。
public partial class coletasEntities : DbContext
{
public override int SaveChanges()
{
ChangeTracker.DetectChanges();
foreach (var change in ChangeTracker.Entries())
{
if (change is auditoria || change.State == EntityState.Detached || change.State == EntityState.Unchanged)
continue;
//Pega o nome da tabela
var entityName = change.Entity.GetType().Name;
//var entityName2 = change.Entity.GetType().BaseType()
if (entityName == "auditoria") continue;
// Get the Table() attribute, if one exists
//TableAttribute tableAttr = change.Entity.GetType().BaseType.Name;
TableAttribute tableAttr = change.Entity.GetType().GetCustomAttributes(typeof(TableAttribute), false).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 : ((TableAttribute)tableAttr[0]).Name;
//string tableName = tableAttr != null ? tableAttr.Name : change.Entity.GetType().Name;
string tableName = tableAttr != null ? tableAttr.Name : change.Entity.GetType().BaseType.Name;
// Get primary key value (If you have more than one key column, this will need to be adjusted)
//string keyName = change.Entity.GetType().GetProperties().Single(p => p.GetCustomAttributes(typeof(KeyAttribute), false).Count() > 0).Name;
if (change.State == EntityState.Added)
{
using (coletasEntities ctx = new coletasEntities())
{
foreach (var prop in change.CurrentValues.PropertyNames)
{
auditoria audit = new auditoria();
audit.campo = prop.ToString();
audit.data = DateTime.Now.Date;
audit.hora = DateTime.Now.ToShortTimeString();
audit.id_registro = 0;
audit.id_usuario = Global.id_usuario;
audit.tabela = tableName;
audit.tipo_operacao = (int)change.State;
audit.valor_antigo = "";
try
{
audit.valor_novo = change.CurrentValues[prop].ToString();
} catch
{
audit.valor_novo = "";
}
ctx.auditoria.Add(audit);
ctx.SaveChanges();
}
}
continue;
}
else if (change.State == EntityState.Deleted)
{
using (coletasEntities ctx = new coletasEntities())
{
foreach (var prop in change.OriginalValues.PropertyNames)
{
auditoria audit = new auditoria();
audit.campo = prop.ToString();
audit.data = DateTime.Now.Date;
audit.hora = DateTime.Now.ToShortTimeString();
audit.id_registro = 0;
audit.id_usuario = Global.id_usuario;
audit.tabela = tableName;
audit.tipo_operacao = (int)change.State;
try
{
audit.valor_antigo = change.OriginalValues[prop].ToString();
}
catch
{
audit.valor_antigo = "";
}
audit.valor_novo = "";
ctx.auditoria.Add(audit);
ctx.SaveChanges();
}
}
continue;
}
else if (change.State == EntityState.Modified)
{
using (coletasEntities ctx = new coletasEntities())
{
foreach (var prop in change.OriginalValues.PropertyNames)
{
auditoria audit = new auditoria();
audit.campo = prop.ToString();
audit.data = DateTime.Now.Date;
audit.hora = DateTime.Now.ToShortTimeString();
audit.id_registro = 0;
audit.id_usuario = Global.id_usuario;
audit.tabela = tableName;
audit.tipo_operacao = (int)change.State;
try
{
audit.valor_antigo = change.OriginalValues[prop].ToString();
}
catch
{
audit.valor_antigo = "";
}
try
{
audit.valor_novo = change.CurrentValues[prop].ToString();
}
catch
{
audit.valor_novo = "";
}
if (audit.valor_antigo != audit.valor_novo)
{
ctx.auditoria.Add(audit);
ctx.SaveChanges();
}
}
}
continue;
}
else
{
// Otherwise, don't do anything, we don't care about Unchanged or Detached entities
}
}
return base.SaveChanges();
}
}
有什么建议吗？
使用此 auditEntry.TableName = entry。Metadata.Relational（）.表名;下面是一个示例：
foreach (var entry in ChangeTracker.Entries())
{
if (entry.Entity is Audit || entry.State == EntityState.Detached ||
entry.State == EntityState.Unchanged)
continue;
var auditEntry = new AuditEntry(entry);
auditEntry.TableName = entry.Metadata.Relational().TableName;
auditEntries.Add(auditEntry);
foreach (var property in entry.Properties)
{
if (property.IsTemporary)
{
auditEntry.TemporaryProperties.Add(property);
continue;
}
string propertyName = property.Metadata.Name;
if (property.Metadata.IsPrimaryKey())
{
auditEntry.KeyValues[propertyName] = property.CurrentValue;
continue;
}
switch (entry.State)
{
case EntityState.Added:
auditEntry.NewValues[propertyName] = property.CurrentValue;
break;
case EntityState.Deleted:
auditEntry.OldValues[propertyName] = property.OriginalValue;
break;
case EntityState.Modified:
if (property.IsModified)
{
auditEntry.OldValues[propertyName] = property.OriginalValue;
auditEntry.NewValues[propertyName] = property.CurrentValue;
}
break;
}
}
}
public class AuditEntry
{
public AuditEntry()
{
Changes = new List<AuditDelta>();
}
public AuditEntry(EntityEntry entry)
{
Entry = entry;
Changes = new List<AuditDelta>();
}
public string CreateUser { get; set; }
public string ActionMessage { get; set; }
public string ActionType { get; set; }
public EntityEntry Entry { get; }
public string TableName { get; set; }
public int ModuleType { get; set; }
public Dictionary<string, object> KeyValues { get; } = new Dictionary<string, object>();
public Dictionary<string, object> ForeignKeyValues { get; } = new Dictionary<string, object>();
public Dictionary<string, object> OldValues { get; } = new Dictionary<string, object>();
public Dictionary<string, object> NewValues { get; } = new Dictionary<string, object>();
public Dictionary<string, object> EnitityNameLabels { get; } = new Dictionary<string, object>();
public List<PropertyEntry> TemporaryProperties { get; } = new List<PropertyEntry>();
public bool HasTemporaryProperties => TemporaryProperties.Any();
public List<AuditDelta> Changes { get; set; }
public string DateTimeStamp { get; set; }
public AuditTrail ToAudit()
{
var audit = new AuditTrail();
audit.tablename = TableName;
audit.actiontype = ActionType;
audit.CreateUser = CreateUser;
audit.moduletype = ModuleType;
audit.actionmessage = ActionMessage;
audit.CreateDate = DateTime.UtcNow;
audit.primarykeyvalues = JsonConvert.SerializeObject(KeyValues);
audit.foreignkeyvalues = ForeignKeyValues.Count == 0 ? null : JsonConvert.SerializeObject(ForeignKeyValues);
audit.oldvalues = OldValues.Count == 0 ? null : JsonConvert.SerializeObject(OldValues);
audit.newvalues = NewValues.Count == 0 ? null : JsonConvert.SerializeObject(NewValues);
audit.enititynamelabels = EnitityNameLabels.Count == 0 ? null : JsonConvert.SerializeObject(EnitityNameLabels);
audit.changes = Changes.Count == 0 ? null : JsonConvert.SerializeObject(Changes);
return audit;
}
}
public class AuditDelta
{
public string FieldName { get; set; }
public string ValueBefore { get; set; }
public string ValueAfter { get; set; }
public int FieldId { get; set; }
}