File uploads

FormData conversion

When making visits that include files (even nested files), Inertia will automatically convert the request data into a FormData object. This is necessary, since that's what's required to submit a multipart/form-data request via XHR.

If you'd like the visit to always use a FormData object, you can force this using the forceFormData option.

Inertia.post('/users', data, {
  forceFormData: true,
})

You can learn more about the FormData interface here.

Note, prior to version 0.8.0, Inertia did not automatically convert requests to FormData, and you'll need to manually do this.

File upload example

Here is an example of uploading a file with Inertia using a form. This example includes both a name text input and an avatar file input.

<template>
  <form @submit.prevent="submit">
    <input type="text" v-model="form.name" />
    <input type="file" @input="form.avatar = $event.target.files[0]" />
    <progress v-if="form.progress" :value="form.progress.percentage" max="100">
      {{ form.progress.percentage }}%
    </progress>
    <button type="submit">Submit</button>
  </form>
</template>

<script>
import { useForm } from '@inertiajs/inertia-vue3'

export default {
  setup () {
    const form = useForm({
      name: null,
      avatar: null,
    })

    function submit() {
      form.post('/users')
    }

    return { form, submit }
  },
}
</script>

This example uses the form helper, since it gives us easy access to the upload progress, but you can do this with a plain Inertia visit as well.

Multipart limitations

Uploading files using a multipart/form-data request is not natively supported in some languages for the put, patch or delete methods. The workaround here is to simply upload files using post instead.

Some frameworks, such as Laravel and Rails, support form method spoofing, which allows you to upload the files using post, but have the framework handle the request as a put or patch request. This is done by including a _method attribute in the data of your request.

Inertia.post(`/users/${user.id}`, {
  _method: 'put',
  avatar: form.avatar,
})