运行已有项目

先初始化

安装node_modules 非常简单， 进入项目目录执行命令
npm install

运行

cd /Users/mrs.liang/Workbench/GeQing/palmscore/client_rn/Score-master

react-native run-ios 
或者
react-native run-android

修改js代码后再次运行

ios模拟器，按快捷键：command+r

常用命令

adb devices  #查看连接设备

问题

无法安装app到ios模拟器的问题

执行react-native run-ios命令编译成功，安装报错：
Installing build/Build/Products/Debug-iphonesimulator/Score.app
An error was encountered processing the command (domain=NSPOSIXErrorDomain, code=2):
Failed to install the requested application
An application bundle was not found at the provided path.
Provide a valid path to the desired application bundle.
Print: Entry, ":CFBundleIdentifier", Does Not Exist

Command failed: /usr/libexec/PlistBuddy -c Print:CFBundleIdentifier build/Build/Products/Debug-iphonesimulator/Score.app/Info.plist
Print: Entry, ":CFBundleIdentifier", Does Not Exist

解决方式：
执行如下命令：
react-native upgrade
react-native run-ios