字串轉化為數字？該如何解決

字串轉化為數字？？？
今天遇到個比較奇怪的現象，很可能是我儲備還不夠吧，包含引號的數位字串轉化為數字時出現了問題

"1000","902865066306","02865066306","SIP Phone","IP Trunk","","trunk20","ON2OFF","1333230069","1333230072","1333230134","65","62","Connected"

上面的為一段資料，接下來操作

$arr = '"1000","902865066306","02865066306","SIP Phone","IP Trunk","","trunk20","ON2OFF","1333230069","1333230072","1333230134","65","62","Connected"';
$arr = explode(',',$arr);
print_r($arr);

列印

Array
(
    [0] => "1000"
    [1] => "902865066306"
    [2] => "02865066306"
    [3] => "SIP Phone"
    [4] => "IP Trunk"
    [5] => ""
    [6] => "trunk20"
    [7] => "ON2OFF"
    [8] => "1333230069"
    [9] => "1333230072"
    [10] => "1333230134"
    [11] => "65"
    [12] => "62"
    [13] => "Connected"
)

我想把數組裡的第九個拿出來來和其他的資料比較，平常把引號包圍的字串轉為數字時就是在後面加個0就ok了，可是，今天不一樣了

echo $arr[8] + 0; //結果為0

我就納悶了，怎麼會為0呢，$arr[8]明明有值啊，於是我又測試了下

$num = "1333230069";
echo $num+0;//1333230069

弄了好久沒明白怎麼回事，後來就用了兩個辦法解決了，一個是用正則把數字提出來，另一個是一開始就把字串裡的雙引號全都替換為空白。

可是疑惑還沒有解決，囉嗦到現在，就是想問問大大們，為什麼上面的做法會出現0的結果，而不是想要的數字。

------解決方案--------------------
var_dump($arr[8]); //string(12) ""1333230069""
var_dump($num); //string(10) "1333230069"

這樣看就清楚了，將 $arr[8] 的首尾雙引號去掉後再運算就對了。
------解決方案--------------------
$a=str_getcsv($arr);
var_dump($a[8]);


------解決方案--------------------
根據你提供的資訊我自己也測試了下：

$arr= Array
(0 => "1000",
    1 => "902865066306",
    2 => "02865066306",
    3 => "SIP Phone",
    4 => "IP Trunk",
    5 => "",
    6 => "trunk20",
    7 => "ON2OFF",
    8 => "1333230069",
    9 => "1333230072",
    10 => "1333230134",
    11 => "65",
    12 => "62",
    13 => "Connected"
);
echo gettype($arr[8])."
";
echo $arr[8]."
";
$str1=$arr[8]+0;
echo gettype($str1)."
";
echo ($str1)."
";

$num = "1333230069";
$num1=($num+0);
echo gettype($num)."
";
echo gettype($num1)."
";
echo $num1;

?>

輸出結果是：
string
1333230069
integer
1333230069
string
integer
1333230069

發現沒有出現樓主的問題。
------解決方案--------------------
沒必要那麼麻煩吧？

$arr = '"1000","902865066306","02865066306","SIP Phone","IP Trunk","","trunk20","ON2OFF","1333230069","1333230072","1333230134","65","62","Connected"';
