DlangIDE

D is a general-purpose, object-orientated programming language with C-like syntax. Since it comes with support for Unicode and it does not require forward declarations or a preprocessor for that matter, D might actually be a better choice for various users when compared to C and C++.
Since it's not exactly a very popular programming language, it should come as no big surprise that there aren't many IDEs that support it. Having said that, you're left with two main options: you can either do some digging and hope to find a D language plugin for your day-to-day, favorite IDE or you could install DlangIDE.
In just a few words, DlangIDE is a bespoke utility for the D language that makes it as straightforward as possible for you to edit, compile and debug software within an intuitive environment.

Packs all the conventional features you can expect from a basic IDE

It sports a visually-non-impressive, yet very functional user interface with a typical layout. Just like is the case with most tools of this sort, there's an all-encompassing toolbar on the upper part of the main window, a workspace explorer (project source tree-view) on the left, and the actual multi-tab code editor on the right.
As expected, it packs everything you could expect from a decent IDE. There's a competent code editor with support for code highlighting, a typical compiler, a debugger, basically, everything you could ever need to write and test D language applications.

Say goodbye to plugins for third-party IDEs and start using this useful app, custom-tailored for the D programming language

More information about the app's current feature set and a few very useful quick start guides are available on the app's official GitHub repository page, and they're well-worth checking out if you don't have a lot of experience working with tools such as this.
All things considered, DlangIDE offers you one of the most convenient ways of dealing with D language code. It looks and works like most IDEs out there, and it's backed up by a fairly decent feature set which should make it the go-to solution for all developers looking to save time and effort while coding in D.