技术问询：什么是react-native link？react-native link命令的用途是什么？

Hey there! Let me break down what react-native link is and why it was (and still is, for older projects) such a lifesaver for React Native developers.

react-native link is a command-line tool bundled with React Native, built to automate the tedious process of linking third-party native dependencies to your project. Back before React Native 0.60 introduced auto-linking, almost every native library required manual setup across both iOS and Android—think copying native code files, updating config files, and double-checking paths. This tool took all that repetitive, error-prone work off your plate.

Here’s the key value it delivers:

• Automates native dependency integration: It automatically adds the library’s native code (like Java/Kotlin files for Android, or Objective-C/Swift files for iOS) to your project’s native directories. No more manually dragging files into android/app/src/main/java or ios/YourAppName—the command handles all that heavy lifting.
• Links asset resources: If a library includes assets like custom fonts, icons, or media files, react-native link will update your Android build.gradle and iOS Info.plist files to register these assets. That means you can use them in your React Native code without manually editing those native config files.
• Simplifies cross-platform setup: Instead of following separate, platform-specific setup guides (each with easy-to-miss steps), this command standardizes the process across both iOS and Android. It cuts down on mistakes and saves tons of time, especially if you’re new to React Native and still getting familiar with native project structures.

Quick side note: If you’re using React Native 0.60 or newer, auto-linking is enabled by default, so you won’t need to run react-native link for most libraries. But it’s still a useful command to know for maintaining older projects or working with niche libraries that don’t support auto-linking yet.

内容的提问来源于stack exchange，提问作者Nguyễn Ngọc Duy