在Golang中创建嵌套地图

Question

I need to create a map as shown below:

package main

import "fmt"

func main() {   
   var data = map[string]interface{}{}  
   data["name"] = "User"    
   data["info"] = map[string]string{}   
   data["info"]["email"] = "[e-mail]"  
   fmt.Println(data)
}

I am trying to create nested maps, but I am getting an error as shown below:

# command-line-arguments./interface.go:9: invalid operation: data["info"]["email"] (type interface {} does not support indexing)

Please provide solution to fix this error. Thanks in advance.

Answer 1

Your data:

var data = map[string]interface{}{}

is a map from string to interface{} so data["info"] is just an interface{} until you assert its type as map[string]string:

data["info"].(map[string]string) // Now you have a map[string]string

Once you have a map[string]string, you can index it as desired:

data["info"].(map[string]string)["email"] = "[e-mail]"  

https://play.golang.org/p/yuyAN9FRCxc