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Golang program to demonstrates how to encode map data into a JSON string.

The below example is to converts a map type into a JSON string. First we need to add the package encoding/json to the list of imports. Then Marshal function of the json package is used to encode Go values into JSON values.
// This sample program demonstrates how to encode map data into a JSON string.

package main

import (
	"fmt"	
	"encoding/json"	// Encoding and Decoding Package
)

func main() {
// Create a map of key/value pairs and parses the data into JSON
	emp := make(map[string]interface{})
	emp["name"] = "Mark Taylor"
	emp["jobtitle"] = "Software Developer"
	emp["phone"] = map[string]interface{}{
	"home": "123-466-799",
	"office": "564-987-654",
	}
	emp["email"] = "markt@gmail.com"

	// Marshal the map into a JSON string.
	empData, err := json.Marshal(emp)	
	if err != nil {
		fmt.Println(err.Error())
		return
	}
	
	jsonStr := string(empData)
	fmt.Println("The JSON data is:")
	fmt.Println(jsonStr)
	
}
C:\golang>go run example37.go
The JSON data is:
{"email":"markt@gmail.com","jobtitle":"Software Developer","name":"Mark Taylor","phone":{"home":"123-466-799","office":"564-987-654"}}

C:\golang>

Here is the syntax for Marshal functions in Go:

func Marshal(v interface{}) ([]byte, error)


Marshal function is good for producing JSON that could be returned in a network response, like a Restfult API. The function Marshal returns two values: the encoded JSON data as slice byte and an error value. Using Marshal , we can also encode the values of struct type as JSON values that will help us to quickly build JSON-based APIs.