thinkphp语法：
$mcardcategory=D('tcardcategory');
$cardcategory_information=$mcardcategory->where("CardNumber='1263' and (ISNULL(IsExchange, '')='' or IsExchange='是')")->select();
原生sql：
SELECT * FROM tcardcategory WHERE ( CardNumber='1263' and (ISNULL(IsExchange, '')='' or IsExchange='是') )；
