go deep copy map

Posted 2022-06-01 oxspirt

 

 

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

　　

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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>