How To Implement NextJS Form Validation With Formik And Zod ?

Last Updated : 16 May, 2024

Form validation is a critical aspect of web development to ensure that user input meets specific criteria before submitting data to the server. Implementing form validation in Next.js can be simplified using Formik, a form library for React, and Zod, a schema validation library. Together, they provide a robust solution for managing form state and validating input data in Next.js applications.

Prerequisites:

Approach to Implement NextJS Form Validation with Formik and Zod

Define the layout and structure of the login form using React components and Formik library.
Specify validation rules for form fields using Zod schema. This includes requirements for the name, email, and message fields.
Display form fields and error messages dynamically.
Connect validation schema with Formik.
When the button is clicked, Formik invokes the onSubmit function, triggering the defined actions such as displaying an alert.

Step 1: Create a NextJS application

npx create-next-app <-ProjectName->

Step 2: Navigate to the Project directory

cd <-ProjectName->

Step 3: Install necessary dependencies and bootstrap for CSS styling.

npm install formik zod zod-formik-adapter  bootstrap

Project Structure:

Screenshot-2024-05-12-102650 — Project Structure

The Updated dependencies in your package.json file is look like:

"dependencies": {
    "bootstrap": "^5.3.3",
    "formik": "^2.4.6",
    "next": "14.2.3",
    "react": "^18",
    "react-dom": "^18",
    "zod": "^3.23.8",
    "zod-formik-adapter": "^1.3.0"
  },

Step 4: Create a folder as components and make a components as LoginForm.tsx

JavaScript

// src/app/components/LoginForm.tsx
import React from "react";
import { TypeOf, object, string } from "zod";
import { Formik, Form, Field } from "formik";
import { toFormikValidationSchema } from "zod-formik-adapter";

type ContactFormInputs = TypeOf<typeof contactFormSchema>

const contactFormSchema = object({
  name: string({
    required_error: "Please enter your name",
  }),
  email: string().email("Please enter a valid email"),
  message: string().min(50).max(1000),
});

const LoginForm = () => {
  return (
    <>
      <Formik<ContactFormInputs>
        initialValues={{
          name: "",
          email: "",
          message: "",
        }}
        onSubmit={(values) => {
          alert("Form is submitted")
          console.log("Form is submitted", values);
        }}
        validationSchema={toFormikValidationSchema(contactFormSchema)}
      >{
          (FormikState) => {
            const errors = FormikState.errors;
            return (
              <div className="card shadow">
                <Form className="card-body">
                  <div className="card-title">Contact Us</div>
                  <div className="d-flex justify-content-between gap-2">
                    <div className="form-group w-100">
                      <label className="form-label">
                        <span className="label-text">Your name</span>
                      </label>
                      <Field
                        type="text"
                        name="name"
                        placeholder="e.g. John Doe"
                        className="form-control"
                      />{!!errors.name && (
                        <div className="form-text text-danger">
                          {errors.name}
                        </div>
                      )}

                    </div>
                    <div className="form-group w-100">
                      <label className="form-label">
                        <span className="label-text">Your email</span>
                      </label>
                      <Field
                        type="text"
                        name="email"
                        placeholder="e.g [email protected]"
                        className="form-control"
                      />
                      {!!errors.email && (
                        <div className="form-text text-danger">
                          {errors.email}
                        </div>
                      )}

                    </div>
                  </div>
                  <div className="form-group">
                    <label className="form-label">
                      <span className="label-text">Your message</span>
                    </label>
                    <Field
                      as="textarea"
                      type="text"
                      name="message"
                      className="form-control h-24"
                      placeholder="Message"
                    />
                    {!!errors.message && (
                      <div className="form-text text-danger">
                        {errors.message}
                      </div>
                    )}

                  </div>
                  <div className="card-actions justify-content-end">
                    <button className="btn btn-primary" type="submit">
                      Submit
                    </button>
                  </div>
                </Form>
              </div>
            )
          }
        }
      </Formik>

    </>
  );
};

export default LoginForm;

JavaScript

// page.js
'use client';
import "bootstrap/dist/css/bootstrap.min.css";
import LoginForm from './components/LoginForm.tsx';
import React from 'react';

export default function Home() {
    return (
        <div className="container">
            <div className="row justify-content-center 
                        align-items-center min-vh-100">
                <div className="col-md-6">
                    <h1 className="text-center mb-4">
                        Welcome to Zod + Formik Tutorial
                    </h1>
                    <LoginForm />
                </div>
            </div>
        </div>
    );
}