如何在PHP中从索引数组创建多维数组？ 我有一个二维数组，它的第一个维度是索引数组，第二个维度是关联数组 在数组中，有一些重复的字段，我想合并它们，而对于其他未重复的字段，我想创建一个三维数组并将它们推到那里 这是我的代码和数组：

整个代码工作正常，只是我的第三维度“datacontractor”字段工作不正常

        <?php
    $array=Array
    (
        "0" => Array
        (
                "sid" => 10,
                "contractorid" => 1,
                "fname" => "hi",
                "lname" => "fam",
                "sname" => "saba",
                "materialname" => "beton",
                "netweight" => 100,
            ),
        "1" => Array
        (
                "sid" => 16,
                "contractorid" => 2,
                "fname" => "a",
                "lname" => "a",
                "sname" => "khoram",
                "materialname" => "kk",
                "netweight" => 200,
            ),
        "2" => Array
        (
                "sid" => 16,
                "contractorid" => 7,
                "fname" => "a",
                "lname" => "a",
                "sname" => "khoram",
                "materialname" => "kk",
                "netweight" => 777,
            ),
        "3" => Array
        (
            "sid" => 10,
            "contractorid" => 5,
            "fname" => "hi",
            "lname" => "fam",
            "sname" => "saba",
            "materialname" => "beton",
            "netweight" => 200,
        ),
        "4" => Array
        (
            "sid" => 10,
            "contractorid" => 8,
            "fname" => "hi",
            "lname" => "fam",
            "sname" => "saba",
            "materialname" => "beton",
            "netweight" => 600,
        ),
        "5" => Array
        (
            "sid" => 15,
            "contractorid" => 9,
            "fname" => "hi",
            "lname" => "fam",
            "sname" => "saba",
            "materialname" => "beton",
            "netweight" => 400,
        ),

    );

    $finalarray[]= array();
    $sidlist= array();
    $arraycount=count($array);
    for($i=0;$i<$arraycount ;$i++) {
        array_push($sidlist,$array[$i]["sid"]);
    }
    $sidlist = array_unique($sidlist);
    $sidlistcount=count($sidlist);
    $sidlist1=array();
    foreach ($sidlist as $m){
        array_push($sidlist1,$m);
    }


    for ($i = 0;$i<$sidlistcount ; $i++){
        $id=$sidlist1[$i];
        $datacontractor[$id]= array();
        for ($j = 0;$j<$arraycount ; $j++){
            if ($id==$array[$j]["sid"]){
                $contractorid = $array[$j]["contractorid"];
                $netweight = $array[$j]["netweight"];
                $finalarray[$i]=array(
                    "sid" => $id,
                    "fname" => $array[$j]["fname"],
                    "lname" => $array[$j]["lname"],
                    "sname" => $array[$j]["sname"],
                    "materialname" => $array[$j]["materialname"],
                    "datacontractor" => $datacontractor[$id],

                );


                $datacontractor[$id]["$contractorid"]=$netweight;
                echo $id,"<br>";
            }

        }
    }

    echo '<pre>';
    print_r($finalarray);
    echo '<pre>';

最后，我想要的结果是： 请检查一下，告诉我什么是我的错

foreach($array as $e) {
    if (!isset($ans[$e['id']])) { // if never set do first time
        $ans[$e['id']] = array("sid" => $e['id'], "datacontractor" => array($e["contractorid"] => [$e["netweight"]])); // notice "contractorid" has array inside (extra "[]" around $e["netweight"])
    } else {
        $ans[$e['id']]["datacontractor"][$e["contractorid"]][] = $e["netweight"]; // append to the contractorid array
    }
}

---

在完成之前，将

“datacontractor”=>$datacontractor[$id]

设置为

finalarray

，将所有数据插入

$datacontractor[$id]

->在单独的循环中执行此操作

你的代码比你实际需要的要复杂得多

考虑以下简短版本：

$data = array_reduce($array, function ($old, $new) {
    if (isset($old[$new['sid']])) {
        $new['datacontractor'] = array_merge($old[$new['sid']]['datacontractor'], [$new['netweight']]);
        $old[$new['sid']] = $new;
    } else {
        $new['datacontractor'] = [$new['netweight']];
    }
    unset($new['netweight']);
    $old[$new['sid']] = $new;
    return $old;
}, []);

$data = array_values($data);
print '<pre>';
print_r($data);
print '</pre>';

现在，

$ans

将输出您的愿望

编辑：

对于将多个

contractorid

值更改为此：

对于重新索引

$ans

请在末尾执行此操作：

$ans=array\u值（$ans）
您可以使用

$data=array\u reduce（$array，function（$old，$new）{
如果（isset（$old[$new['sid']]））{
$new['datacontractor']=数组合并（$old[$new['sid']]['datacontractor']，[$new['netweight']）；
$old[$new['sid']]=$new；
}否则{
$new['datacontractor']=[$new['netweight']]；
}
未设置（$new['netweight']）；
$old[$new['sid']]=$new；
返回$old；
}, []);
$data=数组_值（$data）；
打印“”；
打印（数据）；
打印“”；
这是来自数据库查询吗？现在不是，但以后用SQL而不是PHP来完成这项任务要好得多。您好，我在代码中发现了一个问题…对于特定的
sid
，如果我们有相同的
contractorid
和不同的
netweight
，在输出中，我们只有最后一个，它将被覆盖…例如：
“1”=>数组（“sid”=>16，“contractorid”=>2，“materialname”=>“kk”，“netweight”=>200，），“2”=>数组（“sid”=>16，“contractorid”=>2、“materialname”=>kk、“netweight”=>777、），
在
datacontractor
的输出中，我们只有
2=>777
，但是我们应该有
2=>200
和
2=>777
这样的权利-因为关联数组强制键的唯一性-如果您想要为相同的
contractorid
使用不同的
netweight
，那么
contractorid
字段应该是be另一个数组具有所有
netweight
s（这是您需要的吗？）是的，那么我该怎么办？…还有一些其他问题…当打印
$ans
时，第二个数组的数组索引与
id
s相同，尽管它应该从0开始，并像普通数组一样自动增加。。
$array = []; // this is just some of the fields - you can add all of then here 
$array[] = array("id"=> 10, "contractorid" => 1,"netweight" => 100);
$array[] = array("id"=> 16, "contractorid" => 2,"netweight" => 200);
$array[] = array("id"=> 16, "contractorid" => 7,"netweight" => 777);
$array[] = array("id"=> 10, "contractorid" => 5,"netweight" => 200);
$array[] = array("id"=> 10, "contractorid" => 8,"netweight" => 600);
$array[] = array("id"=> 15, "contractorid" => 9,"netweight" => 400);

$ans = [];
foreach($array as $e) {
    if (!isset($ans[$e['id']])) { // if never set do first time
        $ans[$e['id']] = array("sid" => $e['id'], "datacontractor" => array($e["contractorid"] => $e["netweight"])); // here you can add all your other fields as fname, lname...
    } else {
        $ans[$e['id']]["datacontractor"][$e["contractorid"]] = $e["netweight"]; // just add the new field as already set
    }
}

foreach($array as $e) {
    if (!isset($ans[$e['id']])) { // if never set do first time
        $ans[$e['id']] = array("sid" => $e['id'], "datacontractor" => array($e["contractorid"] => [$e["netweight"]])); // notice "contractorid" has array inside (extra "[]" around $e["netweight"])
    } else {
        $ans[$e['id']]["datacontractor"][$e["contractorid"]][] = $e["netweight"]; // append to the contractorid array
    }
}

$data = array_reduce($array, function ($old, $new) {
    if (isset($old[$new['sid']])) {
        $new['datacontractor'] = array_merge($old[$new['sid']]['datacontractor'], [$new['netweight']]);
        $old[$new['sid']] = $new;
    } else {
        $new['datacontractor'] = [$new['netweight']];
    }
    unset($new['netweight']);
    $old[$new['sid']] = $new;
    return $old;
}, []);

$data = array_values($data);
print '<pre>';
print_r($data);
print '</pre>';