Golang：JSON格式的字节片

Question

I'm new to Go. Currently I have two arrays that look like:

words: ["apple", "banana", "peach"]
freq: [2, 3, 1]

where "freq" stores the count of each word in "words". I hope to combine the two arrays into a Json formatted byte slice that looks like

[{"w":"apple","c":2},{"w":"banana","c":3},{"w":"peach","c":1}]

How can I achieve this goal?

Currently I've declared a struct

type Entry struct {
  w string
  c int
}

and when I loop through the two arrays, I did

  res := make([]byte, len(words))
  for i:=0;i<len(words);i++ {
     obj := Entry{
       w: words[i], 
       c: freq[i],
     }
     b, err := json.Marshal(obj)
     if err==nil {
        res = append(res, b...)
     }
  }

  return res // {}{}{}

which doesn't gives me the desired result. Any help is appreciated. Thanks in advance.

Answer 1

json.Marshal requires the struct fields to be exported.

You can use json tags to have json with small letter keys.

type Entry struct {
  W string `json:"w"`
  C int `json:"c"`
}

Also it would be easier to use a []Entry to generate the output json. Sample code.