# NFCService Data Types NFCService defines and uses several data types. ## NFCMessage An object returned by an NFC `read()` operation. | Property Name | Type | Description | Example | | ----------------- | -------------------- | ------------------------------------------------------------------------------------------------------------ | --------------------------------------------------------------------------- | | `totalByteLength` | Number | The size, in number of bytes, of the data received by the `read()` operation. | 256 | | `records` | `NFCMessageRecord[]` | An array containing a single `NFCMessageRecord` object, which in turn contains the payload from the NFC tag. | `[NFCMessageRecord]` | | `tagInfo` | `NFCTagInfo` | The metadata about the tag. See [`NFCTagInfo`](#nfctaginfo). | `{ serialNumber: "04:EE:A0:5A", isNdefWritable: false, ndefCapacity: 512 }` | ## NFCTagInfo An object within an `NFCMessage` object, containing the metadata read from an NFC tag. | Property Name | Type | Description | Example | | ---------------- | ------- | ---------------------------------------------------------------------------------------------------------------------------------------------------- | ------------- | | `serialNumber` | String | The serial number of the tag. | "04:EE:A0:5A" | | `isNdefWritable` | Boolean | For a tag that can contain NDEF data, indicates whether the tag’s NDEF data can be overwritten. If the tag doesn’t support NDEF, this value is null. | false | | `ndefCapacity` | Number | The maximum NDEF message size, in bytes, that the tag can hold. If the tag doesn’t support NDEF, this value is null. | 512 | ## NFCMessageRecord An object within an `NFCMessage` object, containing the payload read from an NFC tag. | Property Name | Type | Description | Example | | ------------- | ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------- | | `parsed` | `NFCRecord` | Contains the parsed values of the raw data read from the NFC tag. The parsing operation only occurs if the value of the `typeNameFormat` property on the `NFCRecord` object is "WELLKNOWN". Otherwise, this property’s value is null. | | | `raw` | `NFCRecord` | Contains the raw base64 data string read from the NFC tag. | | ## NFCRecord An object containing one record of data from an NFC tag scan. | Property Name | Type | Description | Example | | ---------------- | ---------------- | ------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------- | | `typeNameFormat` | `TypeNameFormat` | The Type Name Format field of the payload, as defined by the NDEF specification. | "WELLKNOWN" See [TypeNameFormat](/docs/platform/lwc/guide/reference-lightning-nfcservice-constants.md) for a list of possible values. | | `type` | String | The type of the payload, as defined by the NDEF specification. | "T" (when payload is of type text); "U" (when payload is of type URI) | | `identifier` | String | The identifier of the payload, as defined by the NDEF specification, or an empty string if no identifier data was present in the tag. | | | `payload` | String | The content of the record, encoded in base64 format. | "V2XigJlyZSBTYWxlc2ZvcmNlLCBG9tZXIgY29tcGFueS4" | ## TextPayload An object containing raw text input, to be converted into an `NFCRecord`. | Property Name | Type | Description | Example | | ------------- | ------ | ---------------------------------------------------------------------------------------------------- | ----------------------------------------- | | `text` | String | The raw text payload to be converted. | "We’re Salesforce, the customer company." | | `langId` | String | The [ISO 639-1](https://quickref.me/iso-639-1.html#list-of-iso-639-1-codes) language ID of the text. | "en" | ## NFCServiceOptions An object containing configuration details for an NFC interaction. | Property Name | Type | Description | Example | | ----------------- | ------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------- | | `instructionText` | String | Optional. Provides instructions to display in the user interface. Defaults to no text. | "Hold your phone near the tag to read." | | `successText` | String | Optional. Provides a message to display in the user interface when an NFC operation is successfully completed. Defaults to no text. | "Tag read successfully!" | | `allowEmptyTags` | Boolean | Optional. Indicates whether reading from an empty tag is considered an error. Defaults to `false`, so attempting to read an empty tag returns a `TAG_EMPTY` error. To get the tag metadata even for empty tags, set this property to `true`. The `read()` operation then returns an `NFCMessage` object whose `tagInfo` property is populated instead of a `TAG_EMPTY` error. | true | ## NFCServiceFailure An object representing an error that occurred when accessing NFCService features. | Property Name | Type | Description | | ------------- | ----------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `code` | `NFCServiceFailureCode` | A value representing the reason for an error. See [`NFCServiceFailureCode`](/docs/platform/lwc/guide/reference-lightning-nfcservice-constants.md#nfcservicefailurecode) for the list of possible values. | | `message` | String | A string value describing the reason for the failure. This value is suitable for use in user interface messages. The message is provided in English and isn’t localized. | **See Also** - [NFCService Constants](/docs/platform/lwc/guide/reference-lightning-nfcservice-constants.md)