arrays - Getting a value of a specific key

Question

This question already has answers here: question from:https://stackoverflow.com/questions/65623296/getting-a-value-of-a-specific-key

Answer 1

package main

import (
    "encoding/json"
    "fmt"
    "log"
)

func main() {
    str := `[{"Key":"a","Value":"4521"},{"Key":"b","Value":"7"}]`

    // declaring out struct we will use for unmarshaling and iteration check.
    out := []struct {
        Key, Value string
    }{}

    if err := json.Unmarshal([]byte(str), &out); err != nil {
        log.Fatal(err)
    } else {
        // searching for value.
        for i := range out {
            if out[i].Key == "b" {
                fmt.Println("Found", out[i].Value)
                return
            }
        }
    }
}

This is an easy way to do that, not optimal. Optimal wound be parse string manually, byte by byte.