php - php 计数函数中的错误计数

Question

$checkvpn = trim(`sudo ifconfig | grep -i "inet addr:" | cut -d ":" -f2 | awk '{print $1}'`);
$checkvpnstring = (string)$checkvpn;
$checkvpncount = count("\n",$checkvpnstring);
$checkvpncount++;
$checkvpnexplode = explode("\n", $checkvpnstring);

for($i=0;$i<=$checkvpncount;$i++){
    $ip = $checkvpnexplode[$i];
    if($ip == $externalip){
        $vpnconfigured = "yes";
        break;
    }
}

我有上面的代码，其中我获得了我的 linux 机器上可用的所有 ip。但是当我有 13 个 ip 并且只计数 3 并且如果我回显 $checkvpnexplode[12] 然后它打印第 13 个 ip 地址时，就会出现问题。

我的问题是，为什么 count 函数只计算 3 而 explode 函数给出所有的输出。
我对 explode 和计数使用了相同的函数。

$checkvpn 的值 = 10.10.1.1 10.10.2.1 103.29.235.45 127.0.0.1

value of $checkvpnstring = 10.10.1.1 10.10.0.1 10.10.8.1 103.29.235.15 10.10.10.1 127.0.0.1 10.10.12.1 10.10.9.1 10.10.11.1 10.10.7.1 10.10.5.1 10.10.2.1 10.10.6.1 10.10.3.1 10.10.4.1

value of $checkvpnstring = 10.10.1.1 10.10.0.1 10.10.8.1 103.29.235.15 10.10.10.1 127.0.0.1 10.10.12.1 10.10.9.1 10.10.11.1 10.10.7.1 10.10.5.1 10.10.2.1 10.10.6.1 10.10.3.1 10.10.4.1

Answer 1

$checkvpncount = count("\n",$checkvpnstring); 是错误的；应该是 $checkvpncount = count($checkvpnstring); 它看起来像是你的 explode 语句中的复制粘贴错误

我已经测试了你的代码并做了一些小改动:

<?
$vpnconfigured = "no";
$externalip = "1.2.3.4";
$checkvpn = trim(`sudo ifconfig | grep -i "inet addr:" | cut -d ":" -f2 | awk '{print $1}'`);
$checkvpnstring = (string)$checkvpn;
$checkvpncount = count($checkvpnstring);
$checkvpncount++;
$checkvpnexplode = explode("\n", $checkvpnstring);

for($i=0;$i<=$checkvpncount;$i++){
    $ip = $checkvpnexplode[$i];
    if($ip == $externalip){
        $vpnconfigured = "yes";
        break;
    }
}
var_dump($checkvpncount);
var_dump($checkvpnexplode);
var_dump($checkvpn);
echo $vpnconfigured;
?>

看来你的计数被额外的参数搞糊涂了；

输出是:

int(2)
array(2) {
  [0]=>
  string(13) "192.168.1.240"
  [1]=>
  string(9) "127.0.0.1"
}
string(23) "192.168.1.240
127.0.0.1"

和我相应的 ifconfig 输出:

eth0      Link encap:Ethernet  HWaddr xx:xx:xx:xx:xx:xx
          inet addr:192.168.1.240  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: xxxx::xxxx:xxxx:xxxx:xxxx/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:6501443 errors:0 dropped:7 overruns:0 frame:21
          TX packets:7860026 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:2026553110 (1.8 GiB)  TX bytes:5197150028 (4.8 GiB)
          Interrupt:18

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:146814 errors:0 dropped:0 overruns:0 frame:0
          TX packets:146814 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:25834701 (24.6 MiB)  TX bytes:25834701 (24.6 MiB)