Scott Hanselman

Can someone make .NET Core better with a simple global command? Fanie Reynders did and he did it in a simple and elegant way. I'm envious, in fact, because I spec'ed this exact thing out in a meeting a few months ago but I could have just done it like he did and I would have used fewer keystrokes!

Last year when .NET Core was just getting started, there was a "DNVM" helper command that you could use to simplify dealing with multiple versions of the .NET SDK on one machine. Later, rather than 'switching global SDK versions,' switching was simplified to be handled on a folder by folder basis. That meant that if you had a project in a folder with no global.json that pinned the SDK version, your project would use the latest installed version. If you liked, you could create a global.json file and pin your project's folder to a specific version. Great, but I would constantly have to google to remember the format for the global.json file, and I'd constantly go into c:\Program Files\dotnet in order to get a list of the currently installed SDKs. I proposed that Microsoft make a "dotnet sdk list" command and the ability to pin down versions like "dotnet sdk 1.0.4" and even maybe install new ones with "dotnet sdk install 2.1.0" or something.

Fanie did all this for us except the installation part, and his implementation is clean and simple. It's so simple that I just dropped his commands into my Dropbox's Utils folder that I have in my PATH on all my machines. Now every machine I dev on has this extension.

UPDATE: There is both a Windows version and a bash version here.

Note that if I type "dotnet foo" the dotnet.exe driver will look in the path for an executable command called dotnet-foo.* and run it.

C:\Users\scott\Desktop>dotnet foo
No executable found matching command "dotnet-foo"

C:\Users\scott\Desktop>dotnet sdk
No executable found matching command "dotnet-sdk"

He created a dotnet-sdk.cmd you can get on his GitHub. Download his repo and put his command somewhere in your path. Now I can do this:

C:\Users\scott\Desktop>dotnet sdk list
The installed .NET Core SDKs are:
1.0.0
1.0.0-preview2-003131
1.0.0-rc3-004530
1.0.2
1.0.4

Which is lovely, but the real use case is this:

C:\Users\scott\Desktop\fancypants>dotnet --version
1.0.4

C:\Users\scott\Desktop\fancypants>dotnet sdk 1.0.0
Switching .NET Core SDK version to 1.0.0

C:\Users\scott\Desktop\fancypants>dotnet --version
1.0.0

C:\Users\scott\Desktop\fancypants>dir
 Volume in drive C is Windows
 Directory of C:\Users\scott\Desktop\fancypants

07/26/2017  04:53 PM                47 global.json
               1 File(s)             47 bytes

Then if I go "dotnet sdk latest" it just deletes the global.json. Perhaps in a perfect world it should just remove the sdk JSON node in case global.json has been modified, but for now it's great. Without the global.json the dotnet.exe will just use your latest installed SDK.

This works with .NET Core 2.0 as well. This should be built-in, but for now it's a very nice example of a clean extension to dotnet.exe.

Oh, and by the way, he also made a ".net.cmd" so you can do this with all your dotnet.exe commands.

Give these commands a try!

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About Scott

Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, consultant, father, diabetic, and Microsoft employee. He is a failed stand-up comic, a cornrower, and a book author.

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