如何在Golang中在运行时动态设置数组的索引？

Question

I have searched a lot about it but couldn't find the proper solution. what I am trying to do is to create the following as final output using arrays and slices in golang.

[
  11 => [1,2,3],
  12 => [4,5],
]

what I have implemented is:

type Industries struct {
    IndustryId  int         `json:"industry_id"`
    FormIds     []int       `json:"form_ids"`
}


var IndustrySettings IndustrySettings
_ := json.NewDecoder(c.Request.Body).Decode(&IndustrySettings)
var industryArr []int

for _, val := range IndustrySettings.IndustrySettings {
    industryArr = append(industryArr, val.IndustryId)   
}

In this IndustrySettings contains following json

{
    "industry_settings": [{
            "industry_id": 11,
            "form_ids": [1, 2, 3]
        },
        {
            "industry_id": 12,
            "form_ids": [4, 5]
        }
    ]
}

I want to loop through this json and convert into the array like industry_id as key and form_ids as values.

Can anyone please tell how to accomplish this?

Thanks!

Edit

I mean I need output like

[
  11 => [1,2,3],
  12 => [4,5],
]

where 11 and 12 are the industry_id as given in the json to be used as key of the array and [1,2,3], [4,5] are the form ids to be set as values in the array.

Answer 1

I think what you might want to do is define a struct that describes the JSON model you are trying to decode, unmarshal the JSON into a slice of that struct, and then loop through each decoded value, placing it in a map.

An example of this is here: https://play.golang.org/p/Dz8XBnoVos