从json_encode输出中删除索引

Question

我一直在搜索这个站点，并且绞尽脑汁试图打印一个不包含索引的json_encode结果。

下面是PHP/MySQL从数据库中获取数据的函数:

public function listGuestsAll() {
if(is_null($this->pdo)) {
$this->msg = 'Connection Failed!';
return [];
} else {
$pdo = $this->pdo;
$stmt = $pdo->prepare('SELECT user_id, name_first, name_last, email_address, user_role FROM guestList');
$stmt->execute();
$result = $stmt->fetchAll(); 
return $result; 
}
}

…下面是print_r代码:

print_r(json_encode($user->listGuestsAll()));

…下面是输出:

[
{
"user_id":"1",
"0":"1",
"name_first":"John",
"1":"John",
"name_last":"Doe",
"2":"Doe",
"email_address":"[e-mail]",
"3":"[e-mail]",
"user_role":"1",
"4":"1"
},
{
"user_id":"2",
"0":"2",
"name_first":"Jane",
"1":"Jane",
"name_last":"Doe",
"2":"Doe",
"email_address":"[e-mail]",
"3":"[e-mail]",
"user_role":"1",
"4":"1"
}]

我如何让它输出没有重复字段索引为0:1,1:John, 2:Doe, 3:john@doe, 4:1等?

提前感谢!

Answer 1

您正在使用它来获取行:

$result = $stmt->fetchAll(); 

文档说明默认的获取模式是PDO::FETCH_BOTH，这意味着返回的结果同时包含作为键和数字键的列名。

可以指定获取模式。要获取仅由数字键索引的行，请使用:

$result = $stmt->fetchAll(PDO::FETCH_NUM); 

要获取仅按列名索引的行，使用:

$result = $stmt->fetchAll(PDO::FETCH_ASSOC); 

你也可以全局改变默认值，这样当你没有指定一个获取模式时，它会影响你所有的获取:

$this->pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_NUM);

你应该读:

• https://www.php.net/manual/en/pdostatement.fetch.php
• https://www.php.net/manual/en/pdostatement.fetchall.php
• https://www.php.net/manual/en/pdo.setattribute.php