忽略SaveChangesAsync

Question

有誰知道如何覆蓋SaveChangesAsync？我知道發佈了類似的問題，但沒有答案。下面我有以下代碼：

public override async Task<int> SaveChangesAsync() 
{ 
    PerformFurtherValidations(); 
    return await base.SaveChangesAsync(); 
} 

在生成過程中我得到了以下錯誤消息：

錯誤SaveChangesAsync（）：返回類型必須是 System.Threading.Tasks.Task<int>匹配重寫的成員 System.Data.Entity.DbContext.SaveChangesAsync()

Answer 1

舊的問題，但我有一個類似的問題，並解決它與以下代碼：

public override async Task<int> SaveChangesAsync() 
    { 
     foreach (var history in this.ChangeTracker.Entries() 
      .Where(e => e.Entity is IModificationHistory && (e.State == EntityState.Added || 
       e.State == EntityState.Modified)) 
      .Select(e => e.Entity as IModificationHistory) 
      ) 
     { 
      history.DateModified = DateTime.Now; 
      if (history.DateCreated <= DateTime.MinValue) 
      { 
       history.DateCreated = DateTime.Now; 
      } 
     } 
     int result = await base.SaveChangesAsync(); 
     foreach (var history in this.ChangeTracker.Entries() 
             .Where(e => e.Entity is IModificationHistory) 
             .Select(e => e.Entity as IModificationHistory)) 
     { 
      history.IsDirty = false; 
     } 
     return result; 
    } 

自定義SaveChangesAsync（）允許我調整髒標誌，創建日期和修改日期。

Answer 2

public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default(CancellationToken)) 
{ 
    return (await base.SaveChangesAsync(true, cancellationToken)); 
}