Submission handling

Passing additional data to submission handling

You may have multiple types of submission behaviour, for example, going back to another page or staying on the form. You can accomplish this by specifying the onSubmitMeta property. This meta data will be passed to the onSubmit function.

Note: if form.handleSubmit() is called without metadata, it will use the provided default.

tsx

import { useForm } from '@tanstack/react-form'

type FormMeta = {
  submitAction: 'continue' | 'backToMenu' | null
}

// Metadata is not required to call form.handleSubmit().
// Specify what values to use as default if no meta is passed
const defaultMeta: FormMeta = {
  submitAction: null,
}

function App() {
  const form = useForm({
    defaultValues: {
      data: '',
    },
    // Define what meta values to expect on submission
    onSubmitMeta: defaultMeta,
    onSubmit: async ({ value, meta }) => {
      // Do something with the values passed via handleSubmit
      console.log(`Selected action - ${meta.submitAction}`, value)
    },
  })

  return (
    <form
      onSubmit={(e) => {
        e.preventDefault()
        e.stopPropagation()
      }}
    >
      {/* ... */}
      <button
        type="submit"
        // Overwrites the default specified in onSubmitMeta
        onClick={() => form.handleSubmit({ submitAction: 'continue' })}
      >
        Submit and continue
      </button>
      <button
        type="submit"
        onClick={() => form.handleSubmit({ submitAction: 'backToMenu' })}
      >
        Submit and back to menu
      </button>
    </form>
  )
}

import { useForm } from '@tanstack/react-form'

type FormMeta = {
  submitAction: 'continue' | 'backToMenu' | null
}

// Metadata is not required to call form.handleSubmit().
// Specify what values to use as default if no meta is passed
const defaultMeta: FormMeta = {
  submitAction: null,
}

function App() {
  const form = useForm({
    defaultValues: {
      data: '',
    },
    // Define what meta values to expect on submission
    onSubmitMeta: defaultMeta,
    onSubmit: async ({ value, meta }) => {
      // Do something with the values passed via handleSubmit
      console.log(`Selected action - ${meta.submitAction}`, value)
    },
  })

  return (
    <form
      onSubmit={(e) => {
        e.preventDefault()
        e.stopPropagation()
      }}
    >
      {/* ... */}
      <button
        type="submit"
        // Overwrites the default specified in onSubmitMeta
        onClick={() => form.handleSubmit({ submitAction: 'continue' })}
      >
        Submit and continue
      </button>
      <button
        type="submit"
        onClick={() => form.handleSubmit({ submitAction: 'backToMenu' })}
      >
        Submit and back to menu
      </button>
    </form>
  )
}

Transforming data with Standard Schemas

While Tanstack Form provides Standard Schema support for validation, it does not preserve the Schema's output data.

The value passed to the onSubmit function will always be the input data. To receive the output data of a Standard Schema, parse it in the onSubmit function:

tsx

const schema = z.object({
  age: z.string().transform((age) => Number(age)),
})

// Tanstack Form uses the input type of Standard Schemas
const defaultValues: z.input<typeof schema> = {
  age: '13',
}

const form = useForm({
  defaultValues,
  validators: {
    onChange: schema,
  },
  onSubmit: ({ value }) => {
    const inputAge: string = value.age
    // Pass it through the schema to get the transformed value
    const result = schema.parse(value)
    const outputAge: number = result.age
  },
})

const schema = z.object({
  age: z.string().transform((age) => Number(age)),
})

// Tanstack Form uses the input type of Standard Schemas
const defaultValues: z.input<typeof schema> = {
  age: '13',
}

const form = useForm({
  defaultValues,
  validators: {
    onChange: schema,
  },
  onSubmit: ({ value }) => {
    const inputAge: string = value.age
    // Pass it through the schema to get the transformed value
    const result = schema.parse(value)
    const outputAge: number = result.age
  },
})

Submission handling

Passing additional data to submission handling

Transforming data with Standard Schemas

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