Question

我有这个任意的多维数组。

Array (

[0] => Array
    (
        [0] => 0
        [1] => 1
        [2] => 2
    )

[5] => Array
    (
        [0] => 0
        [1] => 1
        [2] => 2
    )

[10] => Array
    (
        [0] => 0
        [1] => 1
        [2] => 2
    )

[15] => Array
    (
        [0] => 0
        [1] => 1
        [2] => 2
    )

[1] => Array
    (
        [0] => 2
        [1] => 1
        [2] => 2
    )

[2] => Array
    (
        [0] => 2
        [1] => 1
        [2] => 2
    )

)

我想运行for循环来提取每个子数组的数据。但我不能做一个简单的for循环，因为索引（0,5,10,15,1）是任意的。有没有办法运行for循环然后跳过子数组，如果它是空的？

谢谢！

Answer 1

这将采用$array并循环通过它，回显键你有一个数组中的数组，你可以在foreach中放置一个foreach：

// First we take the main array ($array) and loop though its values
foreach( $array as $main_key =>$sub_array){
    echo $main_key.": <br />\n"; // echo the key, some extra html to format

    // the values of the mainarray are arrays themselves, just loop again:
    foreach($subarray as $sub_key =>$subvalue){
        echo '- '.$subvalue."<br />\n";
    }
}

如果你在foreach中预告，这里有一点陷阱：

foreach($array as $key =>$value){
    foreach($value as $key=>$value){ /* ... */; }
}

这将产生非常奇怪的结果。内部foreach使用相同的参数名称，并且会搞砸所有内容。

在没有增量索引的数组上运行for循环

1 个答案: