yii 取object的值

CArrayDataProvider Object
(
    [keyField] => id
    [rawData] => Array
        (
            [0] => Array
                (
                    [id] => 
                    [ad_cnt] => 1
                    [ad_checking_cnt] => 0
                    [ad_checkend_cnt] => 1
                    [ad_balance] => ￥8953.00
                )

        )

    [_id:CDataProvider:private] => 
    [_data:CDataProvider:private] => Array
        (
            [0] => Array
                (
                    [id] => 
                    [ad_cnt] => 1
                    [ad_checking_cnt] => 0
                    [ad_checkend_cnt] => 1
                    [ad_balance] => ￥8953.00
                )

        )

    [_keys:CDataProvider:private] => Array
        (
            [0] => 
        )

    [_totalItemCount:CDataProvider:private] => 1
    [_sort:CDataProvider:private] => CSort Object
        (
            [multiSort] => 
            [modelClass] => 
            [attributes] => Array
                (
                )

            [sortVar] => sort
            [descTag] => desc
            [defaultOrder] => 
            [route] => 
            [separators] => Array
                (
                    [0] => -
                    [1] => .
                )

            [params] => 
            [_directions:CSort:private] => Array
                (
                )

            [_e:CComponent:private] => 
            [_m:CComponent:private] => 
        )

    [_pagination:CDataProvider:private] => CPagination Object
        (
            [pageVar] => page
            [route] => 
            [params] => 
            [validateCurrentPage] => 1
            [_pageSize:CPagination:private] => 10
            [_itemCount:CPagination:private] => 1
            [_currentPage:CPagination:private] => 0
            [_e:CComponent:private] => 
            [_m:CComponent:private] => 
        )

    [_e:CComponent:private] => 
    [_m:CComponent:private] => 
)


echo $gridDataProvider -> rawData[0]['ad_balance'];