On Wednesday, 29 November 2017 at 11:32:51 UTC, Jayam wrote:
> In D lang,
> [...]
> 3. Can we make library file and use that in any project like 'Util class' ?

Of course ! Plenty of them can be found here: https://code.dlang.org/?sort=updated&category=library

On Tuesday, 28 November 2017 at 13:39:11 UTC, Jayam wrote:
> Can we compile our program to multi program ?

Based on your C# reference you must be referring to the "Mixed Platform" build option. No, that is a .NET thing and D is not on .NET (that project has died).

D requires a more traditional approach to multiple platforms, you'll need to write your code with the needs of your supported platforms in mind. Luckily in pure D this is like no work, but when you interface to C/C++ libraries you'll hit sizes of types and structures changing almost randomly (ok it isn't that bad).