近距离无线通信 (NFC) 概览
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近距离无线通信 (NFC) 是一组近距离无线技术，通常只有在距离不超过 4 厘米时才能启动连接。借助 NFC，您可以在 NFC 标签与 Android 设备之间或者两台 Android 设备之间共享小型负载。
标签的复杂度可能各有不同。简单标签仅提供读取和写入语义，有时可使用一次性可编程区域将卡片设置为只读。较复杂的标签可提供数学运算，还可使用加密硬件来验证对扇区的访问权限。最为复杂的代码包含操作环境，允许与针对代码执行的代码进行复杂的互动。存储在标签中的数据也可以采用多种格式编写，但许多 Android 框架 API 都基于名为 NDEF（NFC 数据交换格式）的 NFC Forum 标准。
支持 NFC 的 Android 设备同时支持以下两种主要操作模式：
- 读取器/写入器模式：支持 NFC 设备读取和写入被动 NFC 标签和贴纸。
- 卡模拟模式：支持 NFC 设备本身充当 NFC 卡。然后，可以通过外部 NFC 读取器（例如 NFC 销售终端）访问模拟 NFC 卡。
- NFC 基础知识
- 本文档介绍了 Android 如何处理发现的 NFC 标签、如何将应用相关数据告知应用以及如何在应用中处理 NDEF 数据，此外还简要介绍了支持 Android 基本 NFC 功能集的框架 API。
- 高级 NFC
- 此文介绍了可使用 Android 支持的各种标签技术的 API。如果您不处理 NDEF 数据，或者需要处理 Android 不一定完全理解的 NDEF 数据，您必须使用自己的协议堆栈以原始字节形式手动读取或写入标签。在这些情况下，Android 支持检测某些标签技术，还支持您使用自己的协议堆栈与标签进行通信。
- 基于主机的卡模拟
- 本文档介绍了 Android 设备如何在不使用安全元件的情况下充当 NFC 卡，同时支持任何 Android 应用模拟卡并直接与 NFC 读取器通信。
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最后更新时间 (UTC)：2025-07-26。
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