編輯:該字符串被輸出和由瀏覽器解釋。愚蠢的錯誤。PHP長度的空字符串32
在我的項目,我創建了一個類來生成我需要的HTML標籤,而回聲大家都出去了我自己。我在名爲Card
的php類中有一個名爲generateTag($control, $isCardValue = true)
的函數。該函數根據通過數組參數$control
傳遞的屬性生成HTML標記。下面是函數的樣子:
public function generateTag($control, $isCardValue = true) {
if ($isCardValue) {
// First we convert the 'class' element to an array
if (isset($control['class']) && gettype($control['class']) !== 'array') {
$control['class'] = array($control['class']);
}
// Then we add the 'card-value' class to that array.
$control['class'][] = 'card-value';
}
// The tag key is mandatory
$tag = '<' . $control['tag'];
// All keys other than 'tag' & 'content' are considered attributes for the HTML tag.
foreach ($control as $key => $value) {
switch ($key) {
case 'tag':
break;
case 'content':
break;
default:
if (gettype($value) === 'array') {
$tag .= ' ' . $key . '="' . implode(' ', $value) . '"';
} elseif (gettype($value) === 'NULL') {
$tag .= ' ' . $key;
} else {
$tag .= ' ' . $key . '="' . $value . '"';
}
break;
}
}
$tag .= '>';
// If the 'content' key is not passed through $control, we assume that the tag
// doesn't need to be closed (e.g. <input> doesn't need a closing tag)
if (isset($control['content'])) {
if (gettype($control['content']) === 'array') {
foreach ($control['content'] as $child) {
$tag .= $this->generateTag($child);
}
} else {
$tag .= $control['content'];
}
$tag .= '</' . $control['tag'] . '>';
}
return $tag;
}
我用這個功能來創建所有的<select>
框<option>
標籤。我只是遍歷數組生成標籤:
foreach ($lists['tags'] as $key => $tag) {
$tag_options[$key] = array(
'tag' => 'option',
'value' => $tag['tag_id'],
'content' => $tag['tag_name_en'],
);
var_dump($card->generateTag($tag_options[$key], false));
}
這就是事情變得怪異。我呼籲生成的字符串的var_dump,我得到下面的輸出:
string(32) "" string(35) "" string(33) "" string(33) "" string(38) "" string(32) "" string(42) "" string(30) "" string(41) "" string(34) "" string(35) "" string(34) "" string(29) "" string(36) "" string(37) "" string(31) "" string(36) "" string(67) "" string(36) "" string(33) "" string(36) "" string(36) ""
看來,它是創造長度的空字符串〜35?最奇怪的是,當我叫substr($tag_options[$key], 0, 1)
,它給了我<
因爲它應該。但是當我打電話給substr($tag_options[$key], 0, 2)
時,它給了我長度爲2的「空」字符串。對發生了什麼事情有所瞭解?
你輸出爲HTML到瀏覽器? 'var_dump'不是HTML編碼。 – Ryan
'
這裏張貼的代碼太多了。我會建議將問題減少到顯示問題的一些線上 - 而不是其他問題。大多數情況下,當你這樣做時,你也會解決你的原始問題 – hek2mgl