将新的键值对添加到JSON对象

Question

I am connecting to an API which gives a rather large json payload. I need to add a key and value to the root object.Once I do ioutil.Readall from the package "net/http" the JSON is a byte array.

My goal is to just simply add to the structure and move on. As an example, the following the pretty similar to what I am doing: https://tutorialedge.net/golang/consuming-restful-api-with-go/

So how can I simply add to a JSON structure another element (key: value)?

Answer 1

If all you want to do is add a key and value to the root object and produce new JSON, and you don't care about having the data in a structure, you can unmarshal into map[string]interface{}, add your value, and then marshal again:

var m map[string]interface{}
err := json.Unmarshal(data, &m)
m["new_key"] = newValue
newData, err := json.Marshal(m)

(I'm not checking for errors, but you should do that of course.) Take a look at https://golang.org/pkg/encoding/json/ for more information about how to deal with JSON in Go.