go deep copy map

 

 

func deepCopyJSON(src map[string]interface{}, dest map[string]interface{}) error {
    if src == nil {
        return errors.New("src is nil. You cannot read from a nil map")
    }
    if dest == nil {
        return errors.New("dest is nil. You cannot insert to a nil map")
    }
    jsonStr, err := json.Marshal(src)
    if err != nil {
        return err
    }
    err = json.Unmarshal(jsonStr, &dest)
    if err != nil {
        return err
    }
    return nil
}

　　

------------------------

How to copy a map to another map?

To copy a map content need to execute a for loop and fetch the index value 1 by 1 with element and assign it to another map. Below is a short example.

 

package main

 

import (

"fmt"

)

func main() {  

    map1 := map[string]int{

        "x":1,

        "y":2,

    }

    map2 := map[string]int{}       

     

    /* Copy Content from Map1 to Map2*/

    for index,element := range map1{       

         map2[index] = element

    }

     

    for index,element := range map2{

        fmt.Println(index,"=>",element) 

    }

}

C:\golang\codes>go run example.go
x => 1
y => 2

C:\golang\codes>