title	description	i18nReady	type
Build forms with API routes	Learn how to use JavaScript to send form submissions to an API Route.	true	recipe

import { Steps } from '@astrojs/starlight/components'; import UIFrameworkTabs from "~~/components/tabs/UIFrameworkTabs.astro"; import PackageManagerTabs from "~~/components/tabs/PackageManagerTabs.astro";

An HTML form causes the browser to refresh the page or navigate to a new one. To send form data to an API endpoint instead, you must intercept the form submission using JavaScript.

This recipe shows you how to send form data to an API endpoint and handle that data.

Prerequisites

A project with SSR (output: 'server' or 'hybrid') enabled
A UI Framework integration installed

Recipe

1. Create a `POST` API endpoint at `/api/feedback` that will receive the form data. Use `request.formData()` to process it. Be sure to validate the form values before you use them.

This example sends a JSON object with a message back to the client.

```ts title="src/pages/api/feedback.ts" "request.formData()" "post"
import type { APIRoute } from "astro";

export const POST: APIRoute = async ({ request }) => {
  const data = await request.formData();
  const name = data.get("name");
  const email = data.get("email");
  const message = data.get("message");
  // Validate the data - you'll probably want to do more than this
  if (!name || !email || !message) {
    return new Response(
      JSON.stringify({
        message: "Missing required fields",
      }),
      { status: 400 }
    );
  }
  // Do something with the data, then return a success response
  return new Response(
    JSON.stringify({
      message: "Success!"
    }),
    { status: 200 }
  );
};
```

Create a form component using your UI framework. Each input should have a name attribute that describes the value of that input.

Be sure to include a <button> or <input type="submit"> element to submit the form.
```tsx title="src/components/FeedbackForm.tsx" export default function Form() { return ( Name Email Message <textarea id="message" name="message" required /> Send ); } ``` ```tsx title="src/components/FeedbackForm.tsx" export default function Form() { return ( Name Email Message <textarea id="message" name="message" required /> Send ); } ``` ```tsx title="src/components/FeedbackForm.tsx" export default function Form() { return ( Name Email Message <textarea id="message" name="message" required /> Send ); } ``` ```svelte title="src/components/FeedbackForm.svelte" Name Email Message <textarea id="message" name="message" required /> Send ``` ```vue title="src/components/FeedbackForm.vue" Name Email Message <textarea id="message" name="message" required /> Send ```

Create a function that accepts a submit event, then pass it as a submit handler to your form.

In the function:

Call preventDefault() on the event to override the browser's default submission process.
Create a FormData object and send it in a POST request to your endpoint using fetch().

```tsx title="src/components/FeedbackForm.tsx" "/api/feedback" add={1, 4-17, 34} add="onSubmit={submit}" "formData" "e.preventDefault();" import { useState } from "preact/hooks";

 export default function Form() {
   const [responseMessage, setResponseMessage] = useState("");

   async function submit(e: SubmitEvent) {
     e.preventDefault();
     const formData = new FormData(e.target as HTMLFormElement);
     const response = await fetch("/api/feedback", {
       method: "POST",
       body: formData,
     });
     const data = await response.json();
     if (data.message) {
       setResponseMessage(data.message);
     }
   }

   return (
     <form onSubmit={submit}>
       <label>
         Name
         <input type="text" id="name" name="name" required />
       </label>
       <label>
         Email
         <input type="email" id="email" name="email" required />
       </label>
       <label>
         Message
         <textarea id="message" name="message" required />
       </label>
       <button>Send</button>
       {responseMessage && <p>{responseMessage}</p>}
     </form>
   );
 }

 ```

```tsx title="src/components/FeedbackForm.tsx" "/api/feedback" add={1, 4-17, 34} add="onSubmit={submit}" "formData" "e.preventDefault();" import { FormEvent, useState } from "react";

 export default function Form() {
   const [responseMessage, setResponseMessage] = useState("");

   async function submit(e: FormEvent<HTMLFormElement>) {
     e.preventDefault();
     const formData = new FormData(e.target as HTMLFormElement);
     const response = await fetch("/api/feedback", {
       method: "POST",
       body: formData,
     });
     const data = await response.json();
     if (data.message) {
       setResponseMessage(data.message);
     }
   }

   return (
     <form onSubmit={submit}>
       <label htmlFor="name">
         Name
         <input type="text" id="name" name="name" autoComplete="name" required />
       </label>
       <label htmlFor="email">
         Email
         <input type="email" id="email" name="email" autoComplete="email" required />
       </label>
       <label htmlFor="message">
         Message
         <textarea id="message" name="message" autoComplete="off" required />
       </label>
       <button>Send</button>
       {responseMessage && <p>{responseMessage}</p>}
     </form>
   );
 }
 ```

```tsx title="src/components/FeedbackForm.tsx" "/api/feedback" add={1, 3-9, 13-19, 36} add="onSubmit={submit}" "formData" "e.preventDefault();" import { createSignal, createResource, Suspense } from "solid-js";

 async function postFormData(formData: FormData) {
   const response = await fetch("/api/feedback", {
     method: "POST",
     body: formData,
   });
   const data = await response.json();
   return data;
 }

 export default function Form() {
   const [formData, setFormData] = createSignal<FormData>();
   const [response] = createResource(formData, postFormData);

   function submit(e: SubmitEvent) {
     e.preventDefault();
     setFormData(new FormData(e.target as HTMLFormElement));
   }

   return (
     <form onSubmit={submit}>
       <label>
         Name
         <input type="text" id="name" name="name" required />
       </label>
       <label>
         Email
         <input type="email" id="email" name="email" required />
       </label>
       <label>
         Message
         <textarea id="message" name="message" required />
       </label>
       <button>Send</button>
       <Suspense>{response() && <p>{response().message}</p>}</Suspense>
     </form>
   );
 }

 ```

```svelte title="src/components/FeedbackForm.svelte" "/api/feedback" add={1-14, 30-32} add="on:submit={submit}" "formData" "e.preventDefault();" <script lang="ts"> let responseMessage: string;

   async function submit(e: SubmitEvent) {
     e.preventDefault();
     const formData = new FormData(e.currentTarget as HTMLFormElement);
     const response = await fetch("/api/feedback", {
       method: "POST",
       body: formData,
     });
     const data = await response.json();
     responseMessage = data.message;
   }
 </script>

 <form on:submit={submit}>
   <label>
     Name
     <input type="text" id="name" name="name" required />
   </label>
   <label>
     Email
     <input type="email" id="email" name="email" required />
   </label>
   <label>
     Message
     <textarea id="message" name="message" required />
   </label>
   <button>Send</button>
   {#if responseMessage}
     <p>{responseMessage}</p>
   {/if}
 </form>
     ```

```vue title="src/components/FeedbackForm.vue" "/api/feedback" add={1-16, 33} "formData" "e.preventDefault();" <script setup lang="ts"> import { ref } from "vue";

 const responseMessage = ref<string>();

 async function submit(e: Event) {
   e.preventDefault();
   const formData = new FormData(e.currentTarget as HTMLFormElement);
   const response = await fetch("/api/feedback", {
     method: "POST",
     body: formData,
   });
   const data = await response.json();
   responseMessage.value = data.message;
 }
 </script>

 <template>
   <form @submit="submit">
     <label>
       Name
       <input type="text" id="name" name="name" required />
     </label>
     <label>
       Email
       <input type="email" id="email" name="email" required />
     </label>
     <label>
       Message
       <textarea id="message" name="message" required />
     </label>
     <button>Send</button>
     <p v-if="responseMessage">{{ responseMessage }}</p>
   </form>
 </template>
 ```

Import and include your <FeedbackForm /> component on a page. Be sure to use a client:* directive to ensure that the form logic is hydrated when you want it to be.
```astro title="src/pages/index.astro" "client:load" --- import FeedbackForm from "../components/FeedbackForm" --- ``` ```astro title="src/pages/index.astro" "client:load" --- import FeedbackForm from "../components/FeedbackForm" --- ``` ```astro title="src/pages/index.astro" "client:load" --- import FeedbackForm from "../components/FeedbackForm" --- ``` ```astro title="src/pages/index.astro" "client:load" --- import FeedbackForm from "../components/FeedbackForm.svelte" --- ``` ```astro title="src/pages/index.astro" "client:load" --- import FeedbackForm from "../components/FeedbackForm.vue" --- ```

{/* ## Extension: Use Zod to validate your form

Zod form data builds on top of Zod to validate your form using a schema. This simplifies your code, as it allows you to declare the fields and their requirements, and let Zod handle the validation.

Install zod and zod-form-data.
```shell npm i zod zod-form-data ``` ```shell pnpm i zod zod-form-data ``` ```shell yarn add zod zod-form-data ```
In your API Route file, declare your schema using zfd.formData and export it. */}

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