声明关联数组时尝试访问另一个字段

Trying to access another field when declaring associative array

假设我有这个:

$data = [
'total' => $itemNull ? 0 : $issueData['workedHours'] * $itemFound->sale_price,
'tax' => $taxRate * $data['total'], 
];

该行抛出 undefined 我明白原因,因为 $data 它没有完全构建我无法访问它。那么问题来了,有什么方法可以访问 'total' 字段吗??

是的,稍后定义。

$data = [
    'total' => $itemNull ? 0 : $issueData['workedHours'] *$itemFound->sale_price,
];

$data['tax'] = $taxRate * $data['total'];

或先定义

$total = $itemNull ? 0 : $issueData['workedHours'] *$itemFound->sale_price;

$data = [
'total' => $total,
'tax' => $taxRate * $total, 
];