问题
I started working on this project on my home PC on Windows 10 using the latest version of Ionic CLI and Typescript and ionic serve works perfectly there.
However after cloning the exact same project to my work PC with Ubuntu which is also running the latest version of Ionic, I get this error when I try to use ionic serve:
"www" directory cannot be found. Please make sure the working directory is an Ionic project.
So obviously now on this PC it's not compiling the Typescript before running it. Somehow on my work PC it thinks this is a plain JS project?
来源：https://stackoverflow.com/questions/45804412/ionic-serve-not-compiling-typescript