1.打开mac的终端
2.输入如下命令
defaults write com.apple.finder AppleShowAllFiles -boolean true ; killall Finder

实现的效果为:

3.还有如何将隐藏文件在隐藏起来:
输入如下命令即可:
defaults write com.apple.finder AppleShowAllFiles -boolean false ; killall Finder
defaults write com.apple.finder AppleShowAllFiles -boolean true ; killall Finder
输入如下命令即可:
defaults write com.apple.finder AppleShowAllFiles -boolean false ; killall Finder