Golang React JS Technology Blog

Different ways to validate JSON string

Check if string is valid JSON
In the below program isJSON function is used to validate given string contains valid JSON or not.

Example

package main

import (
	"encoding/json"
	"fmt"
)

var Object = `{
	"userId": 1,
	"id": 1,
	"title": "delectus aut autem",
	"completed": false
}`
var Array = `[{"key": "value1"}, {"key": "value2"}]`

func isJSON(s string) bool {
	var js interface{}
	return json.Unmarshal([]byte(s), &js) == nil
}

func main() {
	val1 := isJSON(Object)
	fmt.Println(val1)

	val2 := isJSON(Array)
	fmt.Println(val2)
}

Output

true
true
JSON validate using Standard Library function

Example

package main

import (
	"fmt"
	"encoding/json"
)

func main() {
       var tests = []string{
		`"Platypus"`,
		`Platypus`,
		`{"id":"1"}`,
		`{"id":"1}`,
	}

	for _, t := range tests {
		fmt.Printf("Is valid: (%s) = %v\n", t, json.Valid([]byte(t)))
		
	}

}

Output

Is valid: ("Platypus") = true
Is valid: (Platypus) = false
Is valid: ({"id":"1"}) = true
Is valid: ({"id":"1}) = false
Most Helpful This Week
How can I convert a string variable into Boolean, Integer or Float type in Golang? How to read input from console line? User Defined Function Types in Golang Example of Fscan, Fscanf, and Fscanln from FMT Package Split a string at uppercase letters using regular expression in Golang Find element in a slice and move it to first position? Find capacity of Channel, Pointer and Slice How to use function from another file golang? Create and Print Multi Dimensional Slice in Golang How to use for and foreach loop?