javascript - javascript中关联键和数字的数组组合

Question

简而言之，我已经开始我的问题了，

我只是读取json文件，

 [{"FirstCategory":"Bath","SecondCategory":"Bath Accessories","ThirdCategory":""}, {"FirstCategory":"Bath","SecondCategory":"Faucets","ThirdCategory":""},{"FirstCategory":"Bath","SecondCategory":"Fixtures","ThirdCategory":""},{"FirstCategory":"Bath","SecondCategory":"Vanities","ThirdCategory":""},{"FirstCategory":"Building Materials","SecondCategory":"Concrete","ThirdCategory":""},{"FirstCategory":"Building Materials","SecondCategory":"Fencing","ThirdCategory":""},{"FirstCategory":"Building Materials","SecondCategory":"Gypsum","ThirdCategory":""},{"FirstCategory":"Building Materials","SecondCategory":"Insulation","ThirdCategory":""},{"FirstCategory":"Building Materials","SecondCategory":"Insulssdation","ThirdCategory":""}]

并尝试转换为数组，例如

Array
(
  [Bath] => Array
    (
        [Bath Accessories] => Array
            (
                [0] => test
            )

        [Faucets] => Array
            (
                [0] => test1
                [1] => test2
            )

    )

)//sorry i have used PHP for simple formatting the array.

我花了很多时间在这件事上，但我无法取得成功，请帮助我。

 My javascript code : (not working.)

 var FirstCategory = [];
 var SecondCategory = [];
 var ThirdCategory = [];


 $.getJSON('tree.json', function(data) {

var dataObj = new Array();
$.each(data,function(i){
    dataObj[data[i].FirstCategory] = new Array();

    if([data[i].SecondCategory] in dataObj[data[i].FirstCategory])
        dataObj[data[i].FirstCategory][data[i].SecondCategory] = data[i].SecondCategory;
    else
        dataObj[data[i].FirstCategory][data[i].SecondCategory] = new Array();

    dataObj[data[i].FirstCategory][data[i].SecondCategory][data[i].ThirdCategory] = new Array();

});

 console.log(dataObj);

/*
$.each(data,function(i){

    if (FirstCategory == '') {
        FirstCategory.push(data[i].FirstCategory);
    }
    else
    {
        if(!FirstCategory.contains(data[i].FirstCategory))
        {
            //root
            FirstCategory.push(data[i].FirstCategory);
        }
        else
        {
            //------- second level category -------//
            if (SecondCategory == '') {
                SecondCategory.push(data[i].SecondCategory);
            }
            else
            {
                if(!SecondCategory.contains(data[i].SecondCategory))
                {
                    SecondCategory.push(data[i].SecondCategory);
                }
                else
                {
                    ThirdCategory.push(data[i].ThirdCategory);
                }
            }

        }
    }   

});
*/

});


Array.prototype.contains = function(obj) {
  var i = this.length;
  while (i--) {
        if (this[i] == obj) {
         return true;
      }
  }
   return false;
}

提前致谢。

Answer 1

请注意Javascript has no "associative arrays" .

更加编程化:

var levels = ["FirstCategory", "SecondCategory", "ThirdCategory"]; // possibly more
var dataObj = {}; // an empty object
for (var i=0; i<data.length; i++) {
    var cur = dataObj;
    for (var j=0; j<levels.length; j++) {
        var key = data[i][levels[j]];
        if (!key) // empty
            break;
        if (key in cur)
            cur = cur[key];
        else
            cur = cur[key] = {};
    }
}

示例输入的结果 (dataObj)，格式为 JSON:

{
    "Bath": {
        "Bath Accessories": {},
        "Faucets": {},
        "Fixtures": {},
        "Vanities": {}
    },
    "Building Materials": {
        "Concrete": {},
        "Fencing": {},
        "Gypsum": {},
        "Insulation": {},
        "Insulssdation": {}
    }
}