/// <summary>
/// 批量删除
/// </summary>
/// <param name="whereLambda">表达式</param>
/// <param name="isSave">是否保存</param>
/// <returns>受影响的记录数</returns>
public int Delete(Expression <Func <T, bool> > whereLambda, bool isSave = true)
{
return(dal.Delete(whereLambda, isSave));
}