如何在 PHP 中将数据提取到 JSON 编码数组中？

Question

I am trying to fetch some column values (item, description, price etc) into these json_encode arrays.

Inside the arrays you can see the 'amount' string is the one I have attempted on.

I tried using $value = $fetch['price']; and then inside the array using $value but it doesn't accept it.

I also tried..

'amount' => ['price']

&

'amount' => "$fetch['price']"

&

'amount' => `$fetch['price']`

&

'amount' => {$fetch['price']}

I saw some other threads on stackoverflow showing that the fetch query maybe needs to be inside the json_encode ? but that was too fetch all results and encode them whereas I already have the encoding so I'm not sure.

Any help will be appreciated, thanks :)

$userdetails = $_SESSION[usr_name];
$stmt = $dbh->prepare("SELECT * FROM `products` WHERE `username` = '$userdetails' ORDER BY `uid` DESC");
$stmt->execute();
$fetch = $stmt->fetchAll();


$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, 'https://api.commerce.coinbase.com/charges');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode(
array (
'name' => 'My-Business-Name',
'description' => "Selected Product: ",
'local_price' => 
array (
'amount' => $fetch['price'],
'currency' => 'GBP',
),
'pricing_type' => 'fixed_price',
'metadata' => 
array (
'customer_id' => 'uid_1',
'customer_name' => 'Satoshi Nakamoto',
)
));
$result = curl_exec($ch);
curl_close($ch);
$response = json_decode($result, true);

Answer 1

Lets do small refactoring and typo fixes

$userdetails = $_SESSION[usr_name];

It should be either $_SESSION['usr_name'] or $_SESSION[$usr_name] .

Next thing

$stmt = $dbh->prepare("SELECT * FROM `products` WHERE `username` = '$userdetails' ORDER BY `uid` DESC");

The correct and safer way to use prepared statements is next( according to php pdo docs )

$stmt = $dbh->prepare("SELECT * FROM `products` WHERE `username` = :username ORDER BY `uid` DESC");
$stmt->execute(array( ':username' => $userdetails ));
$fetch = $stmt->fetchAll();

After this do something like var_dump or print_r on $fetch just to be sure that data is there as brombeer said.