PHP搜索JSON的价值

所以我有一个json对象,其结构如下：

{
"John Doe": [
    {
        "childName": "Harry","childAge": 15,"childGender": "Male"
    },{
        "childName": "Sally","childAge": 9,"childGender": "Female"
    },],"Miss Piggy": [
    {
        "childName": "Jane","childAge": 20,"childGender": "Female"
    }
],

}

我想要做的是能够查询childName,childAge或childGender,并返回该子对象(如果已找到).

例如：

searchJson($jsonObj,'childName','Sally') // returns {"childName":"Sally","childAge":9,"childGender":"Female"}

在这方面最好的方法是什么？

function searchJson($obj,$field,$value) {
    foreach($obj as $item) {
        foreach($item as $child) {
            if(isset($child->$field) && $child->$field == $value) {
                return $child;
            }
        }
    }
    return null;
}