A class representing the Form API. It handles the logic and interactions with the form state.

Normally, you will not need to create a new FormApi instance directly. Instead, you will use a framework hook/function like useForm or createForm to create a new instance for you that uses your framework's reactivity model. However, if you need to create a new instance manually, you can do so by calling the new FormApi constructor.

• TFormData

• TFormValidator extends Validator<TFormData, unknown> | undefined = undefined

new FormApi<TFormData, TFormValidator>(opts?): FormApi<TFormData, TFormValidator>

new FormApi<TFormData, TFormValidator>(opts?): FormApi<TFormData, TFormValidator>

Constructs a new FormApi instance with the given form options.

• opts?: FormOptions<TFormData, TFormValidator>

FormApi<TFormData, TFormValidator>

packages/form-core/src/FormApi.ts:386

fieldInfo: Record<unknown extends TFormData ? string : TFormData extends readonly any[] & IsTuple<TFormData> ? PrefixTupleAccessor<TFormData<TFormData>, AllowedIndexes<TFormData<TFormData>, never>, []> : TFormData extends any[] ? PrefixArrayAccessor<TFormData<TFormData>, [any]> : TFormData extends Date ? never : TFormData extends object ? PrefixObjectAccessor<TFormData<TFormData>, []> : TFormData extends string | number | bigint | boolean ? "" : never, FieldInfo<TFormData, TFormValidator>>;

fieldInfo: Record<unknown extends TFormData ? string : TFormData extends readonly any[] & IsTuple<TFormData> ? PrefixTupleAccessor<TFormData<TFormData>, AllowedIndexes<TFormData<TFormData>, never>, []> : TFormData extends any[] ? PrefixArrayAccessor<TFormData<TFormData>, [any]> : TFormData extends Date ? never : TFormData extends object ? PrefixObjectAccessor<TFormData<TFormData>, []> : TFormData extends string | number | bigint | boolean ? "" : never, FieldInfo<TFormData, TFormValidator>>;

A record of field information for each field in the form.

packages/form-core/src/FormApi.ts:375

options: FormOptions<TFormData, TFormValidator> = {};

options: FormOptions<TFormData, TFormValidator> = {};

The options for the form.

packages/form-core/src/FormApi.ts:359

state: FormState<TFormData>;

state: FormState<TFormData>;

The current state of the form.

Note: Do not use state directly, as it is not reactive. Please use useStore(form.store) utility to subscribe to state

packages/form-core/src/FormApi.ts:371

store: Store<FormState<TFormData>, (cb) => FormState<TFormData>>;

store: Store<FormState<TFormData>, (cb) => FormState<TFormData>>;

A TanStack Store instance that keeps track of the form's state.

packages/form-core/src/FormApi.ts:363

deleteField<TField>(field): void

deleteField<TField>(field): void

• TField extends string | number

• field: TField

void

packages/form-core/src/FormApi.ts:1116

getFieldInfo<TField>(field): FieldInfo<TFormData, TFormValidator>

getFieldInfo<TField>(field): FieldInfo<TFormData, TFormValidator>

Gets the field info of the specified field.

• TField extends string | number

• field: TField

FieldInfo<TFormData, TFormValidator>

packages/form-core/src/FormApi.ts:1027

getFieldMeta<TField>(field): undefined | FieldMeta

getFieldMeta<TField>(field): undefined | FieldMeta

Gets the metadata of the specified field.

• TField extends string | number

• field: TField

undefined | FieldMeta

packages/form-core/src/FormApi.ts:1018

getFieldValue<TField>(field): DeepValue<TFormData, TField, IsNullable<TFormData>>

getFieldValue<TField>(field): DeepValue<TFormData, TField, IsNullable<TFormData>>

Gets the value of the specified field.

• TField extends string | number

• field: TField

DeepValue<TFormData, TField, IsNullable<TFormData>>

packages/form-core/src/FormApi.ts:1011

handleSubmit(): Promise<void>

handleSubmit(): Promise<void>

Handles the form submission, performs validation, and calls the appropriate onSubmit or onInvalidSubmit callbacks.

Promise<void>

packages/form-core/src/FormApi.ts:952

insertFieldValue<TField>(
   field, 
   index, 
   value, 
opts?): Promise<void>

insertFieldValue<TField>(
   field, 
   index, 
   value, 
opts?): Promise<void>

Inserts a value into an array field at the specified index, shifting the subsequent values to the right.

• TField extends string | number

• field: TField

• index: number

• value: DeepValue<TFormData, TField, IsNullable<TFormData>> extends any[] ? any[] & DeepValue<TFormData, TField, IsNullable<TFormData>>[number] : never

• opts?: UpdateMetaOptions

Promise<void>

packages/form-core/src/FormApi.ts:1148

mount(): void

mount(): void

void

packages/form-core/src/FormApi.ts:513

moveFieldValues<TField>(
   field, 
   index1, 
   index2, 
   opts?): void

moveFieldValues<TField>(
   field, 
   index1, 
   index2, 
   opts?): void

Moves the value at the first specified index to the second specified index within an array field.

• TField extends string | number

• field: TField

• index1: number

• index2: number

• opts?: UpdateMetaOptions

void

packages/form-core/src/FormApi.ts:1266

pushFieldValue<TField>(
   field, 
   value, 
   opts?): void

pushFieldValue<TField>(
   field, 
   value, 
   opts?): void

Pushes a value into an array field.

• TField extends string | number

• field: TField

• value: DeepValue<TFormData, TField, IsNullable<TFormData>> extends any[] ? any[] & DeepValue<TFormData, TField, IsNullable<TFormData>>[number] : never

• opts?: UpdateMetaOptions

void

packages/form-core/src/FormApi.ts:1130

removeFieldValue<TField>(
   field, 
   index, 
opts?): Promise<void>

removeFieldValue<TField>(
   field, 
   index, 
opts?): Promise<void>

Removes a value from an array field at the specified index.

• TField extends string | number

• field: TField

• index: number

• opts?: UpdateMetaOptions

Promise<void>

packages/form-core/src/FormApi.ts:1201

replaceFieldValue<TField>(
   field, 
   index, 
   value, 
opts?): Promise<void>

replaceFieldValue<TField>(
   field, 
   index, 
   value, 
opts?): Promise<void>

Replaces a value into an array field at the specified index.

• TField extends string | number

• field: TField

• index: number

• value: DeepValue<TFormData, TField, IsNullable<TFormData>> extends any[] ? any[] & DeepValue<TFormData, TField, IsNullable<TFormData>>[number] : never

• opts?: UpdateMetaOptions

Promise<void>

packages/form-core/src/FormApi.ts:1175

reset(values?, opts?): void

reset(values?, opts?): void

Resets the form state to the default values. If values are provided, the form will be reset to those values instead and the default values will be updated.

• values?: TFormData

Optional values to reset the form to.

• opts?

Optional options to control the reset behavior.

• opts.keepDefaultValues?: boolean

void

packages/form-core/src/FormApi.ts:580

resetFieldMeta<TField>(fieldMeta): Record<TField, FieldMeta>

resetFieldMeta<TField>(fieldMeta): Record<TField, FieldMeta>

• TField extends string | number

• fieldMeta: Record<TField, FieldMeta>

Record<TField, FieldMeta>

packages/form-core/src/FormApi.ts:1061

setErrorMap(errorMap): void

setErrorMap(errorMap): void

Updates the form's errorMap

• errorMap: ValidationErrorMap

void

packages/form-core/src/FormApi.ts:1290

setFieldMeta<TField>(field, updater): void

setFieldMeta<TField>(field, updater): void

Updates the metadata of the specified field.

• TField extends string | number

• field: TField

• updater: Updater<FieldMeta>

void

packages/form-core/src/FormApi.ts:1046

setFieldValue<TField>(
   field, 
   updater, 
   opts?): void

setFieldValue<TField>(
   field, 
   updater, 
   opts?): void

Sets the value of the specified field and optionally updates the touched state.

• TField extends string | number

• field: TField

• updater: Updater<DeepValue<TFormData, TField, IsNullable<TFormData>>>

• opts?: UpdateMetaOptions

void

packages/form-core/src/FormApi.ts:1085

swapFieldValues<TField>(
   field, 
   index1, 
   index2, 
   opts?): void

swapFieldValues<TField>(
   field, 
   index1, 
   index2, 
   opts?): void

Swaps the values at the specified indices within an array field.

• TField extends string | number

• field: TField

• index1: number

• index2: number

• opts?: UpdateMetaOptions

void

packages/form-core/src/FormApi.ts:1240

update(options?): void

update(options?): void

Updates the form options and form state.

• options?: FormOptions<TFormData, TFormValidator>

void

packages/form-core/src/FormApi.ts:536

validateAllFields(cause): Promise<ValidationError[]>

validateAllFields(cause): Promise<ValidationError[]>

Validates form and all fields in using the correct handlers for a given validation cause.

• cause: ValidationCause

Promise<ValidationError[]>

packages/form-core/src/FormApi.ts:606

validateArrayFieldsStartingFrom<TField>(
   field, 
   index, 
cause): Promise<ValidationError[]>

validateArrayFieldsStartingFrom<TField>(
   field, 
   index, 
cause): Promise<ValidationError[]>

Validates the children of a specified array in the form starting from a given index until the end using the correct handlers for a given validation type.

• TField extends string | number

• field: TField

• index: number

• cause: ValidationCause

Promise<ValidationError[]>

packages/form-core/src/FormApi.ts:640

validateField<TField>(field, cause): ValidationError[] | Promise<ValidationError[]>

validateField<TField>(field, cause): ValidationError[] | Promise<ValidationError[]>

Validates a specified field in the form using the correct handlers for a given validation type.

• TField extends string | number

• field: TField

• cause: ValidationCause

ValidationError[] | Promise<ValidationError[]>

packages/form-core/src/FormApi.ts:679