javascript - 使用 groupby 格式化 Json 对象

Question

我正在尝试通过对城市名称进行分组来格式化 json 对象。我正在尝试采用一个单独的数组并根据找到的和未找到的移动项目来构建字符串。我正在使用 javascript/angularjs 来实现这一点。

我当前的字符串

CurrentDataFormat = 
[
{"Id":17,"code":"123","cityName":"Los Angeles","startDate":"1/20/2016","endDate":"1/20/2016"},

{"Id":18,"code":"456","cityName":"Chicago    ","startDate":"1/22/2016","endDate":"1/25/2016"},

{"Id":19,"code":"789","cityName":"Los Angeles","startDate":"1/13/2016","endDate":"1/21/2016"}
]

我正在尝试实现这种格式

ExpectedDataFormat =

[{
"name":"Los Angeles",
"CityData":
[
{"Id":"17","code":"123","startDate":"1/20/2016","endDate":"1/20/2016"},
{"Id":"19","code":"789","startDate":"1/13/2016","endDate":"1/21/2016"}
]},{
"name":"Chicago",
"CityData":
[
{"Id":"18","code":"456","startDate":"1/22/2016","endDate":"1/25/2016"},
]}

}

逻辑我在尝试什么(尽管尝试使用不同的数据)

var array = [
    { "name": "project1", "url": "picture1-1.jpg"},
    { "name": "project1", "url": "picture1-2.jpg"},
    { "name": "project2", "url": "picture2-1.jpg"},
    { "name": "project3", "url": "picture3-1.jpg"},
    { "name": "project1", "url": "picture1-3.jpg"},
    { "name": "project4", "url": "picture4-1.jpg"},
    { "name": "project3", "url": "picture3-2.jpg"},
    { "name": "project1", "url": "picture1-4.jpg"}
];

var separateArray = [];

$.each(array, function (i, item) {   
    var foundItem = false;
    $.each(separateArray, function (y, newItem) {
        if (newItem.name == item.name) {
            if (!(newItem.url instanceof Array)) {
                newItem.url = [newItem.url];
            }
            newItem.url.push(item.url);
            foundItem = true;
        }
    });

    if (!foundItem) {
     separateArray.push(item);   
    }
});

console.log(separateArray);

Answer 1

这段代码能满足您的需要吗？

var newarray = [];

CurrentDataFormat.forEach(function(item){
    if(newarray[item.cityName] != undefined){
      var key = item.cityName;
      delete item.cityName;
      newarray[key].CityData.push(item);
  }else{
    var o = {};
    o.name = item.cityName;
    o.CityData = [];
    o.CityData.push(item);
    newarray[o.name] = o;
  }
});

console.log(newarray);