/// <summary>
/// 修改表内所有字段
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="entities"></param>
/// <returns></returns>
public virtual Task <int> UpdateEntityList <T>(System.Collections.Generic.ICollection <T> entities) where T : class
{
GetDbSet <T>().UpdateRange(entities.ToArray());
return(SaveChangesAsync());
}