如果API值为空显示默认值

Question

我希望它显示0如果nb_impressions为空

foreach ($content as $row) {
   $impressions = $row['nb_impressions'];
   print("<td'>$impressions</td>");
}

该值来自HTTP API，但是，如果值为空，则显示为空，我该如何给出这些空值0

Answer 1

使用三元操作员检查为

(isset($row['nb_impressions']) && $row['nb_impressions'])并设置默认0

foreach ($content as $row) {
    $impressions = (isset($row['nb_impressions']) && $row['nb_impressions']) ? $row['nb_impressions'] : 0;
    print("<td'>$impressions</td>");
}

评论后，您可以将其组合到检查

的函数中

function isExist($var,$default=''){
    if (isset($var) && $var) {
        return $var;
    }
    return $default;
}

并像这样使用

$impressions = isExist($row['nb_impressions'], 0);
$clicks= isExist($row['nb_clicks'], 0);
$visits = isExist($row['nb_visits'], 0);

Answer 2

您只需添加if语句

foreach ($content as $row) {
   $impressions = $row['nb_impressions'];
   if(isset($impressions)){
       print("<td'>$impressions</td>");
   }else{
       print("<td>0</td>");
   }
}

Answer 3

使用php eatper（）函数检查

foreach ($content as $row) {
   if(!empty($row['nb_impressions'])){
       $impressions = $row['nb_impressions'];
   }
   else{
       $impressions = 0;
   }
   print("<td'>$impressions</td>");
}

直接向前。