Question

我只想从同一级别的同一数组中引用数组的值。甚至有可能，因为在声明数组之后，我可以正确地引用该元素，但是我可以在数组内部进行操作吗？谢谢！

$literature = [
    'authors'=>[ 
        ['name' => 'hhh', 'adress' => 'hemingway@oldtimers.com','yearOfBirth' => '1869'],
        ['name' => 'yyy', 'adress' => 'saintexupéry@oldtimers.com','yearOfBirth' => '1900'],
        ['name' => 'zzz', 'adress' => 'conandoyle@oldtimers.com','yearOfBirth' => '1859']
    ], 
    'books'=>[
        ['title' => 'ggg', 'author' => $literature ['authors'][0]['name'],  'year' => 1943],
        ['title' => 'uuu', 'author' => $literature ['authors'][0]['name'], 'year' => 1887],
        ['title' => 'ttt!', 'author' => $literature ['authors'][0]['name'], 'year' => 1929],
        ['title' => 'vvv', 'author' => $literature ['authors'][0]['name'], 'year' => 1936],
        ['title' => 'ooo', 'author' => $literature ['authors'][0]['name'], 'year' => 1938]
    ]
];

echo $literature ['authors'][0]['name'];// thats a proper reference, that results in showing the value, but when i print the whole array, that value displays as zero
foreach ($literature as $innerKeylevel1 => $innerDatalevel1) {
    foreach ($innerDatalevel1 as $innerKeylevel2 => $innerDatalevel2) {
        foreach ($innerDatalevel2 as $dataKey => $data) {
            echo  $data . " - ";
        }
        echo "</br>";
    }
}

Answer 1

我将从两个数组开始，然后将它们组合。

$authors = [
    ['name' => 'hhh', 'adress' => 'hemingway@oldtimers.com','yearOfBirth' => '1869'],
    ['name' => 'yyy', 'adress' => 'saintexupéry@oldtimers.com','yearOfBirth' => '1900'],
    ['name' => 'zzz', 'adress' => 'conandoyle@oldtimers.com','yearOfBirth' => '1859'],      
];

$books = [
    ['title' => 'ggg', 'author' => $authors ['authors'][0]['name'],  'year' => 1943],
    ['title' => 'uuu', 'author' => $authors ['authors'][0]['name'], 'year' => 1887],
    ['title' => 'ttt!', 'author' => $authors ['authors'][0]['name'], 'year' => 1929],
    ['title' => 'vvv', 'author' => $authors ['authors'][0]['name'], 'year' => 1936],
    ['title' => 'ooo', 'author' => $authors ['authors'][0]['name'], 'year' => 1938]
];

最后：

$literature = [
    'authors'=> $authors,
    'books' => $books,
];

Answer 2

您不能在声明数组的同一部分引用数组-因为表达式是从右到左的（所以它将创建数组，在数组中执行所有操作，并用值 then < / em>将其分配到$literature变量中），这意味着PHP在声明并创建数组之前不知道$literature是什么-为此，您必须在定义数组之后才能使用它。参见PHP: Operator Precedence。手册中关于=赋值运算符

的内容
Associativity | Operators | Additional Information --------------+---------------------------------------------+------------------------- right | = += -= *= **= /= .= %= &= |= ^= <<= >>= | assignment

您可以多次声明它，首先是作者，然后是书籍。

$literature = []; $literature['authors'] = [ ['name' => 'hhh', 'adress' => 'hemingway@oldtimers.com','yearOfBirth' => '1869'], ['name' => 'yyy', 'adress' => 'saintexupéry@oldtimers.com','yearOfBirth' => '1900'], ['name' => 'zzz', 'adress' => 'conandoyle@oldtimers.com','yearOfBirth' => '1859'] ]; $literature['books'] = [ ['title' => 'ggg', 'author' => $literature['authors'][0]['name'], 'year' => 1943], ['title' => 'uuu', 'author' => $literature['authors'][0]['name'], 'year' => 1887], ['title' => 'ttt!', 'author' => $literature['authors'][0]['name'], 'year' => 1929], ['title' => 'vvv', 'author' => $literature['authors'][0]['name'], 'year' => 1936], ['title' => 'ooo', 'author' => $literature['authors'][0]['name'], 'year' => 1938] ]; print_r($literature);

https://3v4l.org/JNtua上的实时演示

如何引用同一数组中的数组元素？

2 个答案: