/// <summary>
/// 将在此上下文中所做的所有更改异步保存到基础数据库。<paramref name="validateOnSaveEnabled"/> 参数指示在调用 SaveChanges() 时，是否应自动验证所跟踪的实体。
/// </summary>
/// <param name="context">表示当前数据库访问上下文 <see cref="System.Data.Entity.DbContext"/> 对象。</param>
/// <param name="cancellationToken">等待任务完成期间要观察的 <see cref="CancellationToken"/>。</param>
/// <param name="validateOnSaveEnabled">指示在调用 SaveChanges() 时，是否应自动验证所跟踪的实体。</param>
/// <returns>表示异步保存操作的任务。任务结果包含已写入基础数据库的对象数目。</returns>
public static Task <int> SaveChangesAsync(this System.Data.Entity.DbContext context, CancellationToken cancellationToken, bool validateOnSaveEnabled)
{
bool enabled = context.Configuration.ValidateOnSaveEnabled;
context.Configuration.ValidateOnSaveEnabled = validateOnSaveEnabled;
try
{
context.Configuration.ValidateOnSaveEnabled = validateOnSaveEnabled;
return(context.SaveChangesAsync(cancellationToken));
}
finally
{
context.Configuration.ValidateOnSaveEnabled = enabled;
}
}
public static async Task <bool> SaveAsync(System.Data.Entity.DbContext context, System.Threading.CancellationToken cancellationToken)
{
System.Data.Entity.Infrastructure.DbUpdateConcurrencyException exception;
try
{
await context.SaveChangesAsync(cancellationToken);
return(true);
}
catch (System.Data.Entity.Infrastructure.DbUpdateConcurrencyException ex)
{
exception = ex;
}
catch (Exception)
{
throw;
}
await exception.Entries.Single().ReloadAsync(cancellationToken);
return(false);
}
