Comment puis-je générer UUID en C#

Attention: bien que les représentations de chaîne pour. NET Guid et (RFC4122) UUID soient identiques, le format de stockage ne l'est pas.. NET se négocie en octets little-endian pour les trois premières parties Guid.

Si vous transmettez les octets (par exemple, en base64), vous ne pouvez pas simplement utiliser Guid.ToByteArray() et l'encoder. Vous aurez besoin de Array.Reverse les trois premières parties (Data1-3).

Je le fais de cette façon:

var rfc4122bytes = Convert.FromBase64String("aguidthatIgotonthewire==");
Array.Reverse(rfc4122bytes,0,4);
Array.Reverse(rfc4122bytes,4,2);
Array.Reverse(rfc4122bytes,6,2);
var guid = new Guid(rfc4122bytes);

Voir cette réponse pour l'implémentation. net spécifique détail.

Edit : Merci à Jeff Walker, Code Ranger, pour avoir souligné que les internes ne sont pas pertinents pour le format du tableau d'octets qui entre et sort du constructeur byte-array et ToByteArray().

Voici une solution "GUID séquentiel" côté client.

Http://www.pinvoke.net/default.aspx/rpcrt4.uuidcreate

using System;
using System.Runtime.InteropServices;


namespace MyCompany.MyTechnology.Framework.CrossDomain.GuidExtend
{
    public static class Guid
    {

        /*

        Original Reference for Code:
        http://www.pinvoke.net/default.aspx/rpcrt4/UuidCreateSequential.html

        */


        [DllImport("rpcrt4.dll", SetLastError = true)]
        static extern int UuidCreateSequential(out System.Guid guid);

        public static System.Guid NewGuid()
        {
            return CreateSequentialUuid();
        }


        public static System.Guid CreateSequentialUuid()
        {
            const int RPC_S_OK = 0;
            System.Guid g;
            int hr = UuidCreateSequential(out g);
            if (hr != RPC_S_OK)
                throw new ApplicationException("UuidCreateSequential failed: " + hr);
            return g;
        }


        /*

        Text From URL above:

        UuidCreateSequential (rpcrt4)

        Type a page name and press Enter. You'll jump to the page if it exists, or you can create it if it doesn't.
        To create a page in a module other than rpcrt4, prefix the name with the module name and a period.
        . Summary
        Creates a new UUID 
        C# Signature:
        [DllImport("rpcrt4.dll", SetLastError=true)]
        static extern int UuidCreateSequential(out Guid guid);


        VB Signature:
        Declare Function UuidCreateSequential Lib "rpcrt4.dll" (ByRef id As Guid) As Integer


        User-Defined Types:
        None.

        Notes:
        Microsoft changed the UuidCreate function so it no longer uses the machine's MAC address as part of the UUID. Since CoCreateGuid calls UuidCreate to get its GUID, its output also changed. If you still like the GUIDs to be generated in sequential order (helpful for keeping a related group of GUIDs together in the system registry), you can use the UuidCreateSequential function.

        CoCreateGuid generates random-looking GUIDs like these:

        92E60A8A-2A99-4F53-9A71-AC69BD7E4D75
        BB88FD63-DAC2-4B15-8ADF-1D502E64B92F
        28F8800C-C804-4F0F-B6F1-24BFC4D4EE80
        EBD133A6-6CF3-4ADA-B723-A8177B70D268
        B10A35C0-F012-4EC1-9D24-3CC91D2B7122



        UuidCreateSequential generates sequential GUIDs like these:

        19F287B4-8830-11D9-8BFC-000CF1ADC5B7
        19F287B5-8830-11D9-8BFC-000CF1ADC5B7
        19F287B6-8830-11D9-8BFC-000CF1ADC5B7
        19F287B7-8830-11D9-8BFC-000CF1ADC5B7
        19F287B8-8830-11D9-8BFC-000CF1ADC5B7



        Here is a summary of the differences in the output of UuidCreateSequential:

        The last six bytes reveal your MAC address 
        Several GUIDs generated in a row are sequential 
        Tips & Tricks:
        Please add some!

        Sample Code in C#:
        static Guid UuidCreateSequential()
        {
           const int RPC_S_OK = 0;
           Guid g;
           int hr = UuidCreateSequential(out g);
           if (hr != RPC_S_OK)
             throw new ApplicationException
               ("UuidCreateSequential failed: " + hr);
           return g;
        }



        Sample Code in VB:
        Sub Main()
           Dim myId As Guid
           Dim code As Integer
           code = UuidCreateSequential(myId)
           If code <> 0 Then
             Console.WriteLine("UuidCreateSequential failed: {0}", code)
           Else
             Console.WriteLine(myId)
           End If
        End Sub




        */








    }
}

Mots-Clés: CreateSequentialUUID SequentialUUID

Je ne connais pas les méthodes; cependant, le type de GUID peut être fait via:

Guid iid = System.Runtime.InteropServices.Marshal.GenerateGuidForType(typeof(IFoo));

Http://msdn.microsoft.com/en-us/library/system.runtime.interopservices.marshal.generateguidfortype.aspx

J'ai un Github Gist avec une implémentation Java comme UUID en C#: https://gist.github.com/rickbeerendonk/13655dd24ec574954366

L'UUID peut être créé à partir des bits les moins et les plus significatifs, tout comme en Java. Il les expose également. L'implémentation a une conversion explicite en GUID et une conversion implicite à partir d'un GUID.