(1) docker exec -u 0 -it d946 /bin/bash
(2) apt-get update
(3)apt-get install sudo
(4)apt-get install yum
(5)sudo rpm -Uvh https://packages.microsoft.com/config/centos/7/packages-microsoft-prod.rpm
(6)
curl https://packages.microsoft.com/keys/microsoft.asc | gpg --dearmor > microsoft.gpg
(7)mv microsoft.gpg /etc/apt/trusted.gpg.d/microsoft.gpg
(8)sh -c 'echo "deb [arch=amd64] https://packages.microsoft.com/repos/microsoft-debian-stretch-prod stretch main" > /etc/apt/sources.list.d/dotnetdev.list'
(9)apt-get update
(10)apt-get install -y dotnet-sdk-3.1