在这种情况下如何使用“和”“if”

Question

这是关于PHP的基本问题。

• 我有MySQL数据库，表名为“users”，这个表包含两列“downloads”和“vip”
• 下载列将计算每个用户的下载，如果它达到6，它将阻止下载。

我的问题是：我想设置不同类型的用户。例如，对于普通用户，他们只能下载6个文件，对于VIP用户，他们只能下载15个文件。

这是我的代码：

$dl_user = gator::getUser($dl_username);
if ($dl_user['downloads'] > 99){
    echo "<script type='text/javascript'>location.href='https://www.example.com/?signup=1&'</script>";
    die;
}

$dl_user = gator::getUser($dl_username);
if ($dl_user['downloads'] > 6){
    echo "<script type='text/javascript'>location.href='https://www.example.com/buynow/'</script>";
die;
}

默认情况下，“没有帐户”的访客用户将无法下载任何内容，我给他们变量“100”，因此它将锁定它。

我正在尝试制作这样的代码：

1. 如果用户是来宾=>链接（此部分有效）
2. 如果用户下载超过6>链接（也是这部分工作）
3. 但是如果用户超过6并且他是VIP并且VIP列是1然后将用户限制为15个文件（这不起作用，我该如何解决？）

Answer 1

您可以将VIP列设置为不同的值以检查用户是否为VIP，例如0 =来宾，1 =成员，2 = VIP ...

    $dl_user = gator::getUser($dl_username);

    if ($dl_user['vip'] == 0){
        // BLOCK ANY download.
    } else if($dl_user['vip'] == 1) {
        // User is a member (allow 6 downloads)
        if($dl_user['downloads'] > 6) {
            //BLOCK the download
        } else {
            //ALLOW download and COUNT
            $dl_user['downloads'] = $dl_user['downloads'] + 1;
        }
    } else if($dl_user['vip'] == 2) {
        // User is a VIP (allow 15 downloads)
        if($dl_user['downloads'] > 15) {
            //BLOCK the download
        } else {
            //ALLOW download and COUNT
            $dl_user['downloads'] = $dl_user['downloads'] + 1;
        }
    } else {
        // User has unknown status (not logged or some error)
    }

如果您需要使用字段下载来保持数据结构以检测用户类型，我建议只验证其是否为6,15或100，并根据该情况阻止或允许下载，但这样您将无法计算下载量使用该领域......

Answer 2

我已经为你编写了代码。我想你了解if else条件。

$dl_user = gator::getUser($dl_username);
if($gustuser){
    echo "<script type='text/javascript'>location.href='https://www.example.com/?signup=1&'</script>";
    die;
}elseif($normaluser && ($dl_user['downloads'] >6 )){
        echo "<script type='text/javascript'>location.href='https://www.example.com/buynow/'</script>";
        die;    
}elseif($vipuser && ($dl_user['downloads'] >15 )){
        echo "<script type='text/javascript'>location.href='https://www.example.com/buynow/'</script>";
        die;    
}

Answer 3

如果你看看PHP logical operators documentation，有一个表格显示PHP中的各种逻辑运算符，其中一个是&&运算符。该运算符的结果是：

如果$ a和$ b都为TRUE，则为TRUE。

考虑到这一点，如果您需要在if语句中检查多个条件，可以使用&&来完成此操作。针对您的问题的可行解决方案可能是：

$dl_user = gator::getUser($dl_username);

if ($dl_user['downloads'] > 99){
    echo "<script type='text/javascript'>location.href='https://www.example.com/?signup=1&'</script>";
    die;
}

if ($dl_user['downloads'] > 6){
    echo "<script type='text/javascript'>location.href='https://www.example.com/buynow/'</script>";
    die;
}

if ($dl_user['downloads'] > 6 && $dl_user['is_vip'] && $dl_user['vip_col'] === 1 {
      // Code that restricts user to 15 files
}

显然在这个例子中组成了关键字is_vip和vip_col，但是如果数据库中有类似的字段，你可以写一个类似于上面的条件。

Answer 4

我会立刻测试我的所有条件，因为只有少数：

$echo = 
// is the user have more than 15 downloads OR have more than 5 but not vip?
$dl_user['downloads'] > 14 || ($dl_user['downloads'] > 5 && $dl_user['vip'] < 1) ? 
//we kick him out
"<script type='text/javascript'>location.href='https://www.example.com/buynow/'</script>" : 
// does he have 100 downloads (guest)
$dl_user['downloads'] > 99 ? 
// get subscribed
"<script type='text/javascript'>location.href='https://www.example.com/?signup=1&'</script>" : 
//is none of the above? He can downloads
false;

// we echo the result if there is one, or we leave;
echo $echo ? $echo : die();

如果VIP可以不止一个，那么你知道他可以下载多少，我会像之前那样计算它

//assuming each vip gives you the right to get 10 more download, I multiply vip by 10
$permited_download = $dl_user[vip] > 0 ? intval($dl_user[vip])*10 : '5';

//then I do the same as the previous exemple but with my calculated variable
$echo = 
// is the user have more than permited downloads (if he's a guest, it's 5) ?
$dl_user['downloads'] > ($permited_download - 1) ? 
//we kick him out
"<script type='text/javascript'>location.href='https://www.example.com/buynow/'</script>" : 
// does he have 100 downloads (guest)
$dl_user['downloads'] > 99 ? 
// get subscribed
"<script type='text/javascript'>location.href='https://www.example.com/?signup=1&'</script>" : 
//is none of the above? He can downloads
false;

// we echo the result if there is one, or we leave;
echo $echo ? $echo : die();