Guid.Empty Field
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
A read-only instance of the Guid structure whose value is all zeros.
public: static initonly Guid Empty;
public static readonly Guid Empty;
staticval mutable Empty : Guid
Public Shared ReadOnly Empty As Guid
Field Value
Remarks
You can compare a GUID with the value of the Guid.Empty field to determine whether a GUID is non-zero. The following example uses the Equality operator to compare two GUID values with Guid.Empty to determine whether they consist exclusively of zeros.
// Create a GUID and determine whether it consists of all zeros.
Guid guid1 = Guid.NewGuid();
Console.WriteLine(guid1);
Console.WriteLine($"Empty: {guid1 == Guid.Empty}\n");
// Create a GUID with all zeros and compare it to Empty.
var bytes = new Byte[16];
var guid2 = new Guid(bytes);
Console.WriteLine(guid2);
Console.WriteLine($"Empty: {guid2 == Guid.Empty}");
// The example displays output like the following:
// 11c43ee8-b9d3-4e51-b73f-bd9dda66e29c
// Empty: False
//
// 00000000-0000-0000-0000-000000000000
// Empty: True
open System
// Create a GUID and determine whether it consists of all zeros.
let guid1 = Guid.NewGuid()
printfn $"{guid1}"
printfn $"Empty: {guid1 = Guid.Empty}\n"
// Create a GUID with all zeros and compare it to Empty.
let bytes = Array.zeroCreate<byte> 16
let guid2 = Guid bytes
printfn $"{guid2}"
printfn $"Empty: {guid2 = Guid.Empty}"
// The example displays output like the following:
// 11c43ee8-b9d3-4e51-b73f-bd9dda66e29c
// Empty: False
//
// 00000000-0000-0000-0000-000000000000
// Empty: True
Module Example
Public Sub Main()
' Create a GUID and determine whether it consists of all zeros.
Dim guid1 As Guid = Guid.NewGuid
Console.WriteLine(guid1)
Console.WriteLine("Empty: {0}", guid1 = Guid.Empty)
Console.WriteLine()
' Create a GUID with all zeros and compare it to Empty.
Dim bytes(15) As Byte
Dim guid2 As New Guid(bytes)
Console.WriteLine(guid2)
Console.WriteLine("Empty: {0}", guid2 = Guid.Empty)
End Sub
End Module
' The example displays output like the following:
' 11c43ee8-b9d3-4e51-b73f-bd9dda66e29c
' Empty: False
'
' 00000000-0000-0000-0000-000000000000
' Empty: True
Applies to
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