javascript - 操作JavaScript数组

我希望你能帮助我。如何从以下位置转换此平面JavaScript数组：

[
    {“州”：“第一州”，“区”：“第一区”，“ local_district_id”：1，“ zone_id”：117，“ center_id”：“ A”，“ center_name”：“ Voting Center First”}，
    {“州”：“第一州”，“区”：“第一区”，“ local_district_id”：2，“ zone_id”：117，“ center_id”：“ B”，“ center_name”：“第二投票中心”}，
    {“州”：“第一州”，“区”：“第一区”，“ local_district_id”：6，“ zone_id”：117，“ center_id”：“ C”，“ center_name”：“ Voting Center Third”}，
]

放入一个嵌套数组，如下所示：

[{
    “ state”：“ First State”，
    “儿童”：[{
        “ district_name”：“第一区”，
        “儿童”：[{
            “ local_district_id”：1，
            “ zone_id”：117，
            “ center_id”：“ A”，
            “ center_name”：“首先投票中心名称”，
        }，{
            “ local_district_id”：2
            “ zone_id”：117，
            “ center_id”：“ B”，
            “ center_name”：“第二投票中心名称”，
        }，{
            “ local_district_id”：6
            “ zone_id”：117，
            “ center_id”：“ C”，
            “ center_name”：“投票中心名称第三”，
        }]
    }]
}]

最佳答案

您可以执行类似的操作以使它在单个循环中工作。不是最漂亮的功能，但它可以完成工作而没有很多额外的开销。

<script>
var original = [
    {"state":"First State","district":"First District","local_district_id":1,"zone_id":117,"center_id":"A","center_name":"Voting Center First"},
    {"state":"Second State","district":"First District","local_district_id":2,"zone_id":117,"center_id":"B","center_name":"Voting Center Second"},
    {"state":"First State","district":"First District","local_district_id":6,"zone_id":117,"center_id":"C","center_name":"Voting Center Third"},
];

var statesUsed = {};
var districtsUsed = {};
var newArray = [];
var stateIndex = 0;
var districtIndex = 0;

for (var i=0,l=original.length;i<l;i++) {
    var state = original[i].state;
    var district = original[i].district;
    var local_district_id = original[i].local_district_id;
    var zone_id = original[i].zone_id;
    var center_id = original[i].center_id;
    var center_name = original[i].center_name;

    if (statesUsed[state] == undefined) {
        statesUsed[state] = stateIndex;
        stateIndex++;
        newArray.push({state : state, children : []});
    }

    districtsUsed[state] = (districtsUsed[state] == undefined) ? {} : districtsUsed[state];

    if (districtsUsed[state][district] == undefined) {
        newArray[statesUsed[state]].children.push({district_name : district, children : []});
        districtsUsed[state][district] = newArray[statesUsed[state]].children.length - 1;
    }

    newArray[statesUsed[state]].children[districtsUsed[state][district]].children.push({
          local_district_id : local_district_id,
          zone_id : zone_id,
          center_id : center_id,
          center_name : center_name
    });


}
</script>