[c#] C# how to create a Guid value?

One field of our struct is Guid type. How to generate a valid value for it?

Guid.NewGuid() will create one

var guid = new Guid();

Hey, its a 'valid', although not very useful, Guid.

(the guid is all zeros, if you don't know. Sometimes this is needed to indicate no guid, in cases where you don't want to use a nullable Guid)

System.Guid desiredGuid = System.Guid.NewGuid();

If you want to create a "desired" Guid you can do

var tempGuid = Guid.Parse("<guidValue>");

where <guidValue> would be something like 1A3B944E-3632-467B-A53A-206305310BAE.

Alternately, if you are using SQL Server as your database you can get your GUID from the server instead. In TSQL:

//Retrive your key ID on the bases of GUID 

declare @ID as uniqueidentifier

SET @ID=NEWID()
insert into Sector(Sector,CID)

Values ('Diry7',@ID)


select SECTORID from sector where CID=@ID

There's also ShortGuid - A shorter and url friendly GUID class in C#. It's available as a Nuget. More information here.

PM> Install-Package CSharpVitamins.ShortGuid

Usage:

Guid guid = Guid.NewGuid();
ShortGuid sguid1 = guid; // implicitly cast the guid as a shortguid
Console.WriteLine(sguid1);
Console.WriteLine(sguid1.Guid);

This produces a new guid, uses that guid to create a ShortGuid, and displays the two equivalent values in the console. Results would be something along the lines of:

ShortGuid: FEx1sZbSD0ugmgMAF_RGHw 
Guid:      b1754c14-d296-4b0f-a09a-030017f4461f

There are two ways

var guid = Guid.NewGuid();

or

var guid = Guid.NewGuid().ToString();

both use the Guid class, the first creates a Guid Object, the second a Guid string.

Guid.NewGuid() creates a new random guid.

To makes an "empty" all-0 guid like 00000000-0000-0000-0000-000000000000.

var makeAllZeroGuID = new System.Guid();

or

var makeAllZeroGuID = System.Guid.Empty;

To makes an actual guid with a unique value, what you probably want.

var uniqueGuID = System.Guid.NewGuid(); 

If you are using this in the Reflection C#, you can get the guid from the property attribute as follows

var propertyAttributes= property.GetCustomAttributes();
foreach(var attribute in propertyAttributes)
{
  var myguid= Guid.Parse(attribute.Id.ToString());
}