php 关联数组添加

<?php
// 创建一个空的关联数组
$associativeArray = array();

// 添加键值对
$associativeArray['name'] = 'John Doe';
$associativeArray['email'] = 'john.doe@example.com';

// 打印数组
print_r($associativeArray);
?>

Array
(
    [name] => John Doe
    [email] => john.doe@example.com
)

<?php
$associativeArray = array(
    'name' => 'John Doe',
    'email' => 'john.doe@example.com'
);

// 检查键名是否存在
if (!isset($associativeArray['age'])) {
    $associativeArray['age'] = 30;
} else {
    echo "Key 'age' already exists.";
}

// 使用 array_merge 保留原有值
$newData = array('age' => 30, 'city' => 'New York');
$associativeArray = array_merge($associativeArray, $newData);

print_r($associativeArray);
?>

Array
(
    [name] => John Doe
    [email] => john.doe@example.com
    [age] => 30
    [city] => New York
)