使用 PHP 构建 JSON 响应 - build json response with php

>我尝试处理具有复杂结构的JSON响应，但多次尝试后我不知道如何管理它。

JSON 响应必须如下所示：

"note": {
      "vote": 3,
      "items":[
        {
            "value": 1,
            "touchArea": {
                "x": 122,
                "y": 173,
                "w": 89,
                "h": 89
            }
        },
        {
            "value": 2,
            "touchArea": {
                "x": 122,
                "y": 283,
                "w": 89,
                "h": 89
            }
        },
        {
            "value": 3,
            "touchArea": {
                "x": 122,
                "y": 390,
                "w": 89,
                "h": 89
            }
        }
      ]

注意："vote"是数组的最大值

作为源，我请求 MYSQL 并得到这个数组（$touch）：

Array ( [0] => V:1,X:122,Y:173,W:89,H:89 [1] => V:2,X:122,Y:283,W:89,H:89 [2] => V:3,X:122,Y:390,W:89,H:89 )

我的问题是：如何使用循环从PHP生成此JSON响应，在此示例中，我们只有3个值，但可能会更多。

您可以使用以下命令编辑和重新保存 json 文件或字符串中的数据。

<?php
    $sInFile  = 'in2.json';
    $sOutFile = 'out2.json';
    $aDevelopers = array();
    $aArtists    = array();
    $aCooks      = array();
    $sRaw       = file_get_contents( $sInFile );
    var_dump( $sRaw );
    // object
    $oData    = json_decode( $sRaw );
    //array
    $aData    = json_decode( $sRaw, 1 );
    $aNote = $aData[ 'note' ];
    $aItems = $aNote[ 'items' ];
var_dump( $aData );
    $iCountData = count( $aItems );
    // Loops through items and set new values.
    for( $i = 0; $i < $iCountData; ++$i )
    {
        $aItem = $aItems[ $i ];
        $aItem[ 'value' ] = 'newvalue';
        $aItem[ 'touchArea' ][ 'x' ] = 3455;
        $aItem[ 'touchArea' ][ 'y' ] = 43;
        $aItems[ $i ] = $aItem;
    }
    $aNote[ 'items' ] = $aItems;
    $aData[ 'note' ] = $aNote;
var_dump( $aData );
    $sNewJson = json_encode( $aData );
    file_put_contents( $sOutFile, $sNewJson );
?>

假设来自MySQL的结果集是一个字符串数组，正如您的问题中所暗示的那样，您需要迭代此结果集，在,上拆分字符串，然后在:上拆分字符串，然后将数据处理成所需的结构，最后转换为json。

鉴于您提供的信息，以下内容应该适合您：

<?php
// your initial result set from mysql - an array of strings
$touch = [
    'V:1,X:122,Y:173,W:89,H:89',
    'V:2,X:122,Y:283,W:89,H:89',
    'V:3,X:122,Y:390,W:89,H:89',
];
// map over each element in your result set...
$items = array_map(function($item) {
    $array = [];
    // first, break each string on `,` to 
    // get an array of elements; e.g:
    // ['V:1', 'X:122', 'Y:173', 'W:89', 'H:89'] etc.
    $itemElements = explode(',', $item);
    // then, iterate over these elements...
    foreach ($itemElements as $itemElement) {
        // explode on `:` and assign as a key value pair
        list($key, $value) = explode(':', $itemElement);
        // then, check the key and add the 
        // value to the array as appropriate
        if ('V' === $key) {
            $array['value'] = $value;
        } else {
            $array['touchArea'][strtolower($key)] = $value;
        }
    }
    return $array;
}, $touch);
// then, build the `$note` array...
$note = [
    'note' => [
        'vote'  => count($items),
        'items' => $items,
    ]
];
// finally, json encode
echo json_encode($note, JSON_PRETTY_PRINT);

这会产生：

{
    "note": {
        "vote": 3,
        "items": [
            {
                "value": "1",
                "touchArea": {
                    "x": "122",
                    "y": "173",
                    "w": "89",
                    "h": "89"
                }
            },
            {
                "value": "2",
                "touchArea": {
                    "x": "122",
                    "y": "283",
                    "w": "89",
                    "h": "89"
                }
            },
            {
                "value": "3",
                "touchArea": {
                    "x": "122",
                    "y": "390",
                    "w": "89",
                    "h": "89"
                }
            }
        ]
    }
}

希望这对:)有所帮助

具有 array_map、explode、array_column 和 max 函数的解决方案：

$touch = ["V:1,X:122,Y:173,W:89,H:89", "V:2,X:122,Y:283,W:89,H:89", "V:3,X:122,Y:390,W:89,H:89"];
$result_arr = ["note" => ["vote" => 0, "items" => []]];  // basic structure
array_map(function($v) use (&$result_arr){
    $arr = explode(",", $v);
    $result = [];
    foreach ($arr as $value) {
        $new_arr = explode(":", $value);
        $key = strtolower($new_arr[0]);
        if ($key == "v"){
            $result["value"] = $new_arr[1];
        } else {
            $result["touchArea"][$key] = $new_arr[1];
        }
    }
    $result_arr["note"]["items"][] = $result;
}, $touch);
// getting max vote
$result_arr["note"]["vote"] = max(array_column($result_arr["note"]["items"], "value"));
$final_json = json_encode($result_arr, JSON_PRETTY_PRINT);