Guid.Empty Campo

Definición

Espacio de nombres:

System

Ensamblado:

System.Runtime.dll

Source:

Guid.cs

Instancia de solo lectura de la estructura Guid cuyo valor es todo ceros.

public: static initonly Guid Empty;

public static readonly Guid Empty;

 staticval mutable Empty : Guid

Public Shared ReadOnly Empty As Guid 

Valor de campo

Guid

Comentarios

Puede comparar un GUID con el valor del Guid.Empty campo para determinar si un GUID no es cero. En el ejemplo siguiente se usa el Equality operador para comparar dos valores GUID con Guid.Empty para determinar si constan exclusivamente de ceros.

// 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