php读取二维数组

<?php
// 创建一个二维数组
$matrix = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]
];

// 读取二维数组
foreach ($matrix as $rowIndex => $row) {
    foreach ($row as $colIndex => $value) {
        echo "Row: $rowIndex, Column: $colIndex, Value: $value\n";
    }
}
?>

<?php
$matrix = [
    [1, 2, 3],
    [4, 5, 6],
    [7, 8, 9]
];

foreach ($matrix as $rowIndex => $row) {
    foreach ($row as $colIndex => $value) {
        if (isset($matrix[$rowIndex][$colIndex])) {
            echo "Row: $rowIndex, Column: $colIndex, Value: $matrix[$rowIndex][$colIndex]\n";
        } else {
            echo "Index out of bounds\n";
        }
    }
}
?>

<?php
$matrix = [
    [1, 2, 3],
    [4, null, 6],
    [7, 8, 9]
];

foreach ($matrix as $rowIndex => $row) {
    foreach ($row as $colIndex => $value) {
        if ($value !== null) {
            echo "Row: $rowIndex, Column: $colIndex, Value: $value\n";
        } else {
            echo "Invalid data at Row: $rowIndex, Column: $colIndex\n";
        }
    }
}
?>