I’m more and more amazed (actually I’m not, this is how life on forum-like communities when moderatorss take over) about which StackOverflow questsions get closed, and which ones stay alive.
It seems the best way is to ask longer questions way beyond what most moderatorss can grasp.
Closed:
Still open:
A great point in the comments of the first question is that
you can technically can write .NET 4.0 / C# 4 applications on a .NET 4.5 / C#5 equiped machine and deploy them on machines that only have .NET 4.0 and C# support.
Don’t. I learned that in the .NET 3.0/3.5 and C# 3.0/2.0 era that combining is bad as the version matrix allows for subtle combinations that are hard to test.
.NET 3.0 with C# 2.0 applications written on a system that had .NET 3.5 and C# 3.0 installed would occasionally fail on systems that only had .NET 3.0 and C# 2.0 installed.
–jeroen