如题，我想这个问题是非常困扰，使用ubuntu 18.04 安装 core net 的朋友，安装官方的安装方法或者是网站大多数博客写的方法，都会提示如下的错误
The following information may help to resolve the situation:
The following packages have unmet dependencies:
dotnet-sdk-2.2 : Depends: aspnetcore-runtime-2.2 (>= 2.2.4) but it is not going to be installed
Depends: dotnet-runtime-2.2 (>= 2.2.4) but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
后面再github 上找到了问题的解决方案
https://github.com/dotnet/core/issues/1400
# NO_PUBKEY EB3E94ADBE1229CF
sudo apt-key adv --keyserver packages.microsoft.com --recv-keys EB3E94ADBE1229CF
# NO_PUBKEY B02C46DF417A0893
sudo apt-key adv --keyserver packages.microsoft.com --recv-keys 52E16F86FEE04B979B07E28DB02C46DF417A0893
sudo sh -c 'echo "deb [arch=amd64] https://packages.microsoft.com/repos/microsoft-ubuntu-bionic-prod bionic main" > /etc/apt/sources.list.d/dotnetdev.list'
sudo apt update
sudo apt install dotnet-sdk-2.1
