Question

I've got something but still it isn't working like I want it to work.

I've got an array

    $values = array(
    $aV=>$aP, 
    $bV=>$bP, 
    $cV=>$cP, 
    $dV=>$dP
);

then I sort it like this ` arsort($values);

the result is Array ( [geel] => 28 [groen] => 20 [rood] => 20 [blauw] => 12 )

Now I want to acces the first / second / tird / fourth element to pass it on So I want $values[0] to be the first element. In this case Geel 28. But if I try to echo $values[0] it says Undefined offset: 0 (same with 1/2/3 etc). Obviously because I've got no [0] set but how can I set [0] to the first element in the array (which is different each time. the value geel isn't always [0] but I need the first element (with the lowest number) to be [0] so I can echo $values[0] to be the first element of the array with the lowest number

Answer 1

如果您需要访问索引和数组的值，那么foreach循环可以为您做到这一点

$values = array($aV=>$aP,  $bV=>$bP,  $cV=>$cP, $dV=>$dP );

foreach ( $values as $idx => $val ) {
    echo "Index is $idx and value is $val";
}

使用此数组作为示例

Array ( [geel] => 28 [groen] => 20 [rood] => 20 [blauw] => 12 )

输出将是

Index is geel and value is 28
Index is groen and value is 20
Index is rood and value is 20
Index is blauw and value is 12

Answer 2

因为数组键已设置为geel，groen ..您无法访问$ values [0]，$ values [1]。

您必须访问：

第一个元素：$values['geel'] 第二个要素：$values['groen']等......

Answer 3

要将值和键作为数字索引访问，您需要使用array_values和array_keys

<强>阵列：

$values = array(
    $aV=>$aP, 
    $bV=>$bP, 
    $cV=>$cP, 
    $dV=>$dP
);

对于值：

$new_values = array_values($values);

结果：

array($aP, $bP, $cP, $dP);

对于键：

$keys = array_keys($values);

结果：

array($aV, $bV, $cV, $dV);

现在，您可以将数组作为数字键访问，例如：$keys[0]或$new_values[0]，依此类推。

Answer 4

不要使用＆＃34;箭头＆＃34;制作阵列的指标，您可能希望这样做：

$values = array(
    $aV . ' ' . $aP,
    $bV . ' ' . $bP,
    $cV . ' ' . $cP,
    $dV . ' ' . $dP,
);

您目前正在做的是创建一个看起来像这样的数组

[
    'Geel' => 28
    // etc.
]

如果您真的想获得第一个元素的值，可以使用array_shift

access first element of array

4 个答案: