编辑您的包。Json为你的javascript版本

"react-native": "^0.50.1",

后运行

npm install

I've never seen this error before, but whenever I can't get Xcode and React-Native to play well together, I do a couple of things. Check what version of Xcode I'm working with. If it needs to be updated, I update it. Then clearing watchman and the cache are the second place I go. I don't use the reset cache command. It always says that I need to verify the cache, so I skip that (you can do it though, I just get confused). I use rm -rf $TMPDIR/react-* to get rid of any cached builds. If that doesn't work, I try to build the app in Xcode, then work my way from there, to build it with react-native run-ios. With this error message, it seems you might start by trying to build it with Xcode. Hope that helps...let me know your progress with it. Good luck! (Also, you could update to RN 0.51 as another attempt to get your versions synced.)

我试图从WebStorm中构建和运行一个React Native应用程序，然后遇到了这个问题。对我来说，简单的解决方案是:

watchman watch-del-all

在macOS上，如果watchman还没有安装，请使用Homebrew安装:

brew install watchman

对于那些无法通过关闭和重建来修复的Android开发人员，在模拟器/设备上手动卸载应用程序。

还要确保在模拟器中启用了wifi

对于我的情况下，我在iOS上面临它，我试图重置和清除所有缓存使用以下命令，但失败了，尽管许多评论说，根本原因是有react打包器在某处意外运行，我重新启动了我的mac，问题仍然存在。

watchman watch-del-all && rm -rf node_modules/ && yarn cache clean && yarn install && yarn start --reset-cache

解决方案是，删除build文件夹@ /ios/build，然后执行react-native run-ios解决了它