/// <summary>
/// 新增一个实体对象到数据库中
/// </summary>
/// <param name="entity">需要保存的实体对象</param>
/// 前置条件:
/// 1.参数entity不允许为空
public void Add(object entity)
{
//断言参入的参数为null或者空字符串（RErrorCode.NullReference - 0x00000001）
PreconditionAssert.IsNotNull(entity, ErrorMessages.NullReferenceException);
ORMHelper.EntityIsMappingDatabase(entity.GetType(), ErrorMessages.EntityMappingError);
ORMHelper.CheckEntityIsNotReadOnly(entity.GetType(), ErrorMessages.EntityReadOnly);
InsertCommandCreator icc = new InsertCommandCreator(_dbAccess);
icc.Entity = entity;
DbCommand dbCommand = icc.GetDbCommand();
_dbAccess.ExecCommand(dbCommand);
}