php - PHP循环抛出通知，这似乎是一个持续的错误

Question

$features[] = array("Feature 1", "Feature 2", "Feature 3", "Feature 4")

for ($i=0; $i <4 ; $i++) {
echo '<li class="list-group-item text-centre">'.  $features[i] . '</li>';

我无法解决该通知:

Notice: Use of undefined constant i - assumed 'i' in /home3/..../public_html/html......com/all/stripe/index.php on line 48

Answer 1

这是$features[]的原因。
采用:

$features = array("Feature 1", "Feature 2", "Feature 3", "Feature 4")

$features[]表示您要将 =之后的值传递到 $features数组的新索引中，即 $features[0][your_array]
和
echo '<li class="list-group-item text-centre">'。 $ features [ $ i ]。 '</li>';

替换为

echo '<li class="list-group-item text-centre">'.  $features[$i] . '</li>';