Turn multiple bool values (from HTML form) into a string (Go)

I know the title is really bad, but not sure how to ask this question.. I have a HTML form with a select input returning multiple values, e.g.:

<select name="rights" multiple>
  <option value="create">create</option>
  <option value="view">view</option>
  <option value="edit">edit</option>
  <option value="delete">delete</option>
</select>

I then have a function that can check which values the form contains:

func formContains(slice []string, item string) bool {
    set := make(map[string]struct{}, len(slice))
    for _, s := range slice {
        set
展开收缩
 = struct{}{}
    }
    _, ok := set[item]
    return ok
}

so I can call:

err := r.ParseForm()
// err check
rights := r.Form["rights"]
log.Println(formContains(rights, "create"))

What I would like to do is to check which values the form contains, and then return a string, e.g., if the form contains the rights "create" and "delete" then it should return:
"1001", if it contains the rights "view", "edit" and "delete" then it should return "0111".

I would be able to achieve the desired result with a lot of if/else or switch statements, but I know there must be a smarter way.. I considered the possibility of creating an array that would end up looking like this: [0] 1 [0] 1 (in case the rights were "view" and "delete"), and then convert the array to a string.. but so far it's been unsuccessful..

I think you should look into the bitwise operations topic. There is no need to keep an array, your four operations can be represented as integers instead:

create = 1 (0001 in binary representation)
view   = 2 (0010 in binary representation)
edit   = 4 (0100 in binary representation)
delete = 8 (1000 in binary representation)

In order get all selected rights you can use bitwise OR operation:

rights := 0
rights |= 2
rights |= 4
// rights is 6 now, i.e. view and edit

Then when you need to check if specific right is enabled, you can use bitwise AND opration:

func hasPermission(rights int, item int) bool {
    return (rights & item) == item 
}

See my complete example: https://play.golang.org/p/UPZkqsrDS4

package main

import (
	"fmt"
)


func main() {
	create := 1
	view   := 2
	edit   := 4
	delete := 8
	
	rights := 0
	rights |= view
	rights |= edit


	fmt.Println(hasPermission(rights , create))
	fmt.Println(hasPermission(rights , view))
	fmt.Println(hasPermission(rights , edit))
	fmt.Println(hasPermission(rights , delete))
}


func hasPermission(rights int, item int) bool {
	return (rights & item) == item 
}

Perhaps something like

keys := []string{"create", "view", "edit", "delete"}
b := 0
for idx, key := range keys {
	if len(r.Form[key]) != 0 {
		b += 1 << uint(idx)
	}
}
fmt.Printf("%04b", b)

use s := fmt.Sprintf("%04b", b) to store the "binari rights string" into an string variable.