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  "title" : "NFCNDEFReaderSession"
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# NFCNDEFReaderSession

A reader session for detecting NFC Data Exchange Format (NDEF) tags.

```
class NFCNDEFReaderSession
```

## Overview

As with the [`NFCReaderSession`](/documentation/CoreNFC/NFCReaderSession-swift.class) base class, only one NFC NDEF reader session can be active in the system at a time. If you create an additional session, the system puts it in a queue and processes it in first-in, first-out (FIFO) order.

## Topics

### Creating a Session

[`init(delegate:queue:invalidateAfterFirstRead:)`](/documentation/CoreNFC/NFCNDEFReaderSession/init(delegate:queue:invalidateAfterFirstRead:))

Creates and initializes a new NFC NDEF reader session.

[`NFCNDEFReaderSessionDelegate`](/documentation/CoreNFC/NFCNDEFReaderSessionDelegate)

A protocol that an object implements to serve as an NDEF reader session delegate.

### Connecting to a Tag

[`connect(to:completionHandler:)`](/documentation/CoreNFC/NFCNDEFReaderSession/connect(to:completionHandler:))

Connects the reader session to a tag and activates that tag.

### Restarting the Polling Sequence

[`restartPolling()`](/documentation/CoreNFC/NFCNDEFReaderSession/restartPolling())

Restarts the polling sequence so the reader session can discover new tags.


---

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