我遇到以下代码问题:
w = widgets.Dropdown(
options=['Addition', 'Multiplication', 'Subtraction'],
value='Addition',
description='Task:',
)
def on_change(change):
if change['type'] == 'change' and change['name'] == 'value':
print "changed to %s" % change['new']
w.observe(on_change)
display(w)
在此之前,一切似乎都很好:
# THIS FUNCTION CONNECTS TO MY DATABASE
function createSQLconnection(&$connection) {
$connection = mysqli_connect("typical", "yaddayadda", "crap");
// mysql_select_db("db", $connection);
if (!$connection) {
return "500";
} else {
return "200";
}
}
# THIS FUNCTION GETS ALL LOGS FROM MY DATABASE
function getLogs($conn, &$list, &$length) {
$sql = 'SELECT * FROM `db`.`logs`';
$result = mysqli_query($conn, $sql);
if (mysqli_num_rows($result) > 0) {
$i = 0;
while($row=mysqli_fetch_assoc($result)) {
$list[$i] = $row;
$i++;
}
$length = $i;
}
}
createSQLconnection($conn);
getLogs($conn, $logList, $logLength);
完全没有错误,没有问题,只有没有文字。
当我转储数组时,更令人困惑的是:
for($row=0; $row<$logLength; $row++) {
echo $logList['photo_id'][$row];
echo $logList['name'][$row];
echo $logList['location'][$row];
}
一切都很好:
print_r($logList);
我真的不明白。应该这么简单。难道我做错了什么?我可能错过了什么?