How to sort using statement of C# code in vim?

Question

Recently I edit C# code in vim. And the build system has StyleCop enabled so that all using statement should be in alphabetical order.

So, I tried to select below lines of code in visual mode, then type ":sort".

using System.Security.Permissions;
using System.Runtime.Serialization;
using System.Security;
using System.ServiceModel;

The result is:

using System.Runtime.Serialization;
using System.Security.Permissions;
using System.Security;
using System.ServiceModel;

It doesn't pass StyleCop checking because "System.Security" is not ahead of "System.Security.Permissions". The ASCII value of ";" is larger than ASCII value of ".".

The preferred result is:

using System.Runtime.Serialization;
using System.Security;
using System.Security.Permissions;
using System.ServiceModel;

How to achieve it?

Answer 1

:h :sort is your friend:

:[range]sort r /[^;]*/

If along the way you wish to remove duplicates, add the uniq flag:

:[range]sort ur /[^;]*/

(This won't do any good if you have different comments after the ';' though)

Answer 2

:1,4s/;$//
:sort
:1,4s/$/;/

(where 1,4 are lines with using statements)