Golang : How to get struct tag and use field name to retrieve data?
Problem :
A structure data field can have additional information or meta-data. This information is known as struct tag in Golang. You want to find out a struct data field type's struct tag. How to that with the reflect
package?
NOTE : Don't confuse field name and struct tag yeah!
Solution :
Use the reflect package StructField type to retrieve the data.
Here you go !
package main
import (
"fmt"
"reflect"
)
type Person struct {
Name string `json:name`
}
func getStructTag(f reflect.StructField) string {
return string(f.Tag)
}
func main() {
user := &Person{"Adam"}
field, ok := reflect.TypeOf(user).Elem().FieldByName("Name") // not json:name
if !ok {
panic("Field not found")
}
// get the struct field tag
// see http://golang.org/pkg/reflect/#StructField
fmt.Println(getStructTag(field)) // json:name
//----- get data from the initialized Person struct
//----- based on the field name
r := reflect.ValueOf(user)
f := reflect.Indirect(r).FieldByName("Name")
fmt.Println(f)
}
Output :
json:name
Adam
Happy coding !
References :
See also : Golang : How to get struct field and value by name
By Adam Ng
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