Toolbox-XToolbox-X
GuardsDOM Guards

Check FormData

Checks if a value is a valid non-empty FormData instance.

isValidFormData

Checks if a value is a valid non-empty FormData instance.

Function Signature

isValidFormData(value: unknown): value is FormData

Parameters

  • value: The value to check

Returns

true if:

  • Value is a FormData instance
  • Has entries (not empty)
  • Supports .entries() method

Example

playground.ts

SSR Note

⚠️ May not work in SSR environments like Next.js Server Components

Last updated: Tue, May 26, 2026 04:14:18PM (UTC)

Check UTC Offset

Type guard that checks if a value is a valid UTC offset string.

Check File or Blob

Checks if a given value is an instance of File or Blob.

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isValidFormDataFunction SignatureParametersReturnsExample