Guid 结构

表示全局唯一标识符 (GUID)。

**命名空间:**System
**程序集:**mscorlib（在 mscorlib.dll 中）

语法

声明
<SerializableAttribute> _
<ComVisibleAttribute(True)> _
Public Structure Guid
    Implements IFormattable, IComparable, IComparable(Of Guid), _
    IEquatable(Of Guid)
用法
Dim instance As Guid

[SerializableAttribute] 
[ComVisibleAttribute(true)] 
public struct Guid : IFormattable, IComparable, IComparable<Guid>, 
    IEquatable<Guid>

[SerializableAttribute] 
[ComVisibleAttribute(true)] 
public value class Guid : IFormattable, IComparable, IComparable<Guid>, 
    IEquatable<Guid>

/** @attribute SerializableAttribute() */ 
/** @attribute ComVisibleAttribute(true) */ 
public final class Guid extends ValueType implements IFormattable, IComparable, 
    IComparable<Guid>, IEquatable<Guid>

JScript 支持使用结构，但不支持进行新的声明。

备注

GUID 是一个 128 位整数（16 字节），可用于所有需要唯一标识符的计算机和网络。此标识符重复的可能性非常小。

示例

下面的代码示例说明如何在用户定义的类或接口上作为属性附加和读取 Guid 对象。

Imports System
Imports System.Runtime.InteropServices

' Guid for the interface IMyInterface.
<Guid("F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4")> _
Interface IMyInterface
    Sub MyMethod()
End Interface

' Guid for the coclass MyTestClass.
<Guid("936DA01F-9ABD-4d9d-80C7-02AF85C822A8")> _
Public Class MyTestClass
    Implements IMyInterface
    
    ' Run regasm on this assembly to create .reg and .tlb files.
    ' Reg file can be used to register this coclass in the registry.
    ' Tlb file will be used to do interop.
    Public Sub MyMethod() Implements IMyInterface.MyMethod
    End Sub
    
    Public Shared Sub Main()
        ' Example addresses the following in System.Runtime.InterOpServices.GuidAttribute.
        ' How to specify the attribute on interface/coclass.
        ' Retrieve the GuidAttribute from an interface/coclass.
        ' Value property on GuidAttribute class.
        ' Example addresses the following in System.Guid.
        ' Constructor Guid(string).
        ' Constructor Guid(ByteArray).
        ' Equals.
        ' Operator ==.
        ' CompareTo.
        Dim IMyInterfaceAttribute As Attribute = Attribute.GetCustomAttribute(GetType(IMyInterface), GetType(GuidAttribute))
        
        ' The Value property of GuidAttribute returns a string. 
        System.Console.WriteLine("IMyInterface Attribute: " + CType(IMyInterfaceAttribute, GuidAttribute).Value)
        
        ' Using the string to create a guid.
        Dim myGuid1 As New Guid(CType(IMyInterfaceAttribute, GuidAttribute).Value)
        ' Using a byte array to create a guid.
        Dim myGuid2 As New Guid(myGuid1.ToByteArray())
        
        ' Equals is overridden and so value comparison is done though references are different.
        If myGuid1.Equals(myGuid2) Then
            System.Console.WriteLine("myGuid1 equals myGuid2")
        Else
            System.Console.WriteLine("myGuid1 not equals myGuid2")
        End If 
        ' Equality operator can also be used to determine if two guids have same value.
        If myGuid1.ToString() = myGuid2.ToString() Then
            System.Console.WriteLine("myGuid1 == myGuid2")
        Else
            System.Console.WriteLine("myGuid1 != myGuid2")
        End If
        ' CompareTo returns 0 if the guids have same value.
        If myGuid1.CompareTo(myGuid2) = 0 Then
            System.Console.WriteLine("myGuid1 compares to myGuid2")
        Else
            System.Console.WriteLine("myGuid1 does not compare to myGuid2")
        End If 
        
        System.Console.ReadLine()

        'Output:
        'IMyInterface Attribute: F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4
        'myGuid1 equals myGuid2
        'myGuid1 == myGuid2
        'myGuid1 compares to myGuid2
    End Sub
End Class

using System;
using System.Runtime.InteropServices;

// Guid for the interface IMyInterface.
[Guid("F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4")]
interface IMyInterface
{
    void MyMethod();
}

// Guid for the coclass MyTestClass.
[Guid("936DA01F-9ABD-4d9d-80C7-02AF85C822A8")]
public class MyTestClass : IMyInterface
{
    // Run regasm on this assembly to create .reg and .tlb files.
    // Reg file can be used to register this coclass in the registry.
    // Tlb file will be used to do interop.

    public void MyMethod() {}

    public static void Main( string []args )
    {
        // Example addresses the following in System.Runtime.InterOpServices.GuidAttribute.
        // How to specify the attribute on interface/coclass.
        // Retrieve the GuidAttribute from an interface/coclass.
        // Value property on GuidAttribute class.

        // Example addresses the following in System.Guid.
        // Constructor Guid(string).
        // Constructor Guid(ByteArray).
        // Equals.
        // Operator ==.
        // CompareTo.

        Attribute IMyInterfaceAttribute = Attribute.GetCustomAttribute( typeof( IMyInterface ), typeof( GuidAttribute ) );
        
        // The Value property of GuidAttribute returns a string. 
        System.Console.WriteLine( "IMyInterface Attribute: " + ((GuidAttribute)IMyInterfaceAttribute).Value );    

        // Using the string to create a guid.
        Guid myGuid1 = new Guid( ((GuidAttribute)IMyInterfaceAttribute).Value );
        // Using a byte array to create a guid.
        Guid myGuid2 = new Guid ( myGuid1.ToByteArray() );

        // Equals is overridden and so value comparison is done though references are different.
        if ( myGuid1.Equals( myGuid2 ) )
            System.Console.WriteLine( "myGuid1 equals myGuid2" );
        else
            System.Console.WriteLine( "myGuid1 not equals myGuid2" );

        // Equality operator can also be used to determine if two guids have same value.
        if ( myGuid1 == myGuid2 )
            System.Console.WriteLine( "myGuid1 == myGuid2" );
        else
            System.Console.WriteLine( "myGuid1 != myGuid2" );
    
        // CompareTo returns 0 if the guids have same value.
        if ( myGuid1.CompareTo( myGuid2 ) == 0 )
            System.Console.WriteLine( "myGuid1 compares to myGuid2" );
        else
            System.Console.WriteLine( "myGuid1 does not compare to myGuid2" );

        System.Console.ReadLine();

        //Output.
        //IMyInterface Attribute: F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4
        //myGuid1 equals myGuid2
        //myGuid1 == myGuid2
        //myGuid1 compares to myGuid2
    }
}

using namespace System;
using namespace System::Runtime::InteropServices;

// Guid for the interface IMyInterface.

[Guid("F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4")]
public interface class IMyInterface
{
public:
   void MyMethod();
};


// Guid for the coclass MyTestClass.

[Guid("936DA01F-9ABD-4d9d-80C7-02AF85C822A8")]
public ref class MyTestClass: public IMyInterface
{
public:

   // Run regasm on this assembly to create .reg and .tlb files.
   // Reg file can be used to register this coclass in the registry.
   // Tlb file will be used to do interop.
   virtual void MyMethod(){}
};

int main()
{
   // Example addresses the following in System.Runtime.InterOpServices.GuidAttribute.
   // How to specify the attribute on interface/coclass.
   // Retrieve the GuidAttribute from an interface/coclass.
   // Value property on GuidAttribute class.
   // Example addresses the following in System.Guid.
   // Constructor Guid(string).
   // Constructor Guid(ByteArray).
   // Equals.
   // Operator ==.
   // CompareTo.
   Attribute^ IMyInterfaceAttribute = Attribute::GetCustomAttribute( IMyInterface::typeid, GuidAttribute::typeid );

   // The Value property of GuidAttribute returns a string. 
   System::Console::WriteLine( String::Concat(  "IMyInterface Attribute: ", (dynamic_cast<GuidAttribute^>(IMyInterfaceAttribute))->Value ) );

   // Using the string to create a guid.
   Guid myGuid1 = Guid(dynamic_cast<GuidAttribute^>(IMyInterfaceAttribute)->Value);

   // Using a byte array to create a guid.
   Guid myGuid2 = Guid(myGuid1.ToByteArray());

   // Equals is overridden and so value comparison is done though references are different.
   if ( myGuid1.Equals( myGuid2 ) )
      System::Console::WriteLine(  "myGuid1 equals myGuid2" );
   else
      System::Console::WriteLine(  "myGuid1 not equals myGuid2" );

   // Equality operator can also be used to determine if two guids have same value.
   if ( myGuid1 == myGuid2 )
      System::Console::WriteLine(  "myGuid1 == myGuid2" );
   else
      System::Console::WriteLine(  "myGuid1 != myGuid2" );

   // CompareTo returns 0 if the guids have same value.
   if ( myGuid1.CompareTo( myGuid2 ) == 0 )
      System::Console::WriteLine(  "myGuid1 compares to myGuid2" );
   else
      System::Console::WriteLine(  "myGuid1 does not compare to myGuid2" );

   //Output.
   //IMyInterface Attribute: F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4
   //myGuid1 equals myGuid2
   //myGuid1 == myGuid2
   //myGuid1 compares to myGuid2
}

import System.*;
import System.Runtime.InteropServices.*;

// Guid for the interface IMyInterface.
/** @attribute Guid("F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4")
 */
interface IMyInterface
{
    void MyMethod();
} //IMyInterface

// Guid for the coclass MyTestClass.
/** @attribute Guid("936DA01F-9ABD-4d9d-80C7-02AF85C822A8")
 */
public class MyTestClass implements IMyInterface
{
    // Run regasm on this assembly to create .reg and .tlb files.
    // Reg file can be used to register this coclass in the registry.
    // Tlb file will be used to do interop.
    public void MyMethod()
    {
    } //MyMethod

    public static void main(String[] args)
    {
        // Example addresses the following in System.Runtime.
        // InterOpServices.GuidAttribute.
        // How to specify the attribute on interface/coclass.
        // Retrieve the GuidAttribute from an interface/coclass.
        // Value property on GuidAttribute class.
        // Example addresses the following in System.Guid.
        // Constructor Guid(string).
        // Constructor Guid(ByteArray).
        // Equals.
        // Operator ==.
        // CompareTo.
        Attribute iMyInterfaceAttribute = 
                  Attribute.GetCustomAttribute(IMyInterface.class.ToType(), 
                  GuidAttribute.class.ToType());

        // The Value property of GuidAttribute returns a string. 
        System.Console.WriteLine("IMyInterface Attribute: " 
            + ((GuidAttribute)(iMyInterfaceAttribute)).get_Value());

        // Using the string to create a guid.
        Guid myGuid1 = 
             new Guid(((GuidAttribute)(iMyInterfaceAttribute)).get_Value());
        // Using a byte array to create a guid.
        Guid myGuid2 = new Guid(myGuid1.ToByteArray());
        // Equals is overridden and so value comparison is done though 
        // references are different.
        if (myGuid1.Equals(myGuid2)) {
            System.Console.WriteLine("myGuid1 equals myGuid2");
        }
        else {
            System.Console.WriteLine("myGuid1 not equals myGuid2");
        }
        // Equality operator can also be used to determine if two 
        // guids have same value.
        if (myGuid1 == myGuid2) {
            System.Console.WriteLine("myGuid1 == myGuid2");
        }
        else {
            System.Console.WriteLine("myGuid1 != myGuid2");
        }
        // CompareTo returns 0 if the guids have same value.
        if (myGuid1.CompareTo(myGuid2) == 0) {
            System.Console.WriteLine("myGuid1 compares to myGuid2");
        }
        else {
            System.Console.WriteLine("myGuid1 does not compare to myGuid2");
        }
        System.Console.ReadLine();
    } //main 
} //MyTestClass 

//Output.
//IMyInterface Attribute: F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4
//myGuid1 equals myGuid2
//myGuid1 == myGuid2
//myGuid1 compares to myGuid2

import System;
import System.Runtime.InteropServices;

// Guid for the interface IMyInterface.
Guid("F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4") interface IMyInterface
{
    function MyMethod();
}

// Guid for the coclass MyTestClass.
public Guid("936DA01F-9ABD-4d9d-80C7-02AF85C822A8") class MyTestClass implements IMyInterface
{
    // Run regasm on this assembly to create .reg and .tlb files.
    // Reg file can be used to register this coclass in the registry.
    // Tlb file will be used to do interop.

    public function MyMethod() {}

    public static function Main()
    {
        // Example addresses the following in System.Runtime.InterOpServices.GuidAttribute.
        // How to specify the attribute on interface/coclass.
        // Retrieve the GuidAttribute from an interface/coclass.
        // Value property on GuidAttribute class.

        // Example addresses the following in System.Guid.
        // Constructor Guid(string).
        // Constructor Guid(ByteArray).
        // Equals.
        // Operator ==.
        // CompareTo.

        var IMyInterfaceAttribute : Attribute = Attribute.GetCustomAttribute(Type.GetType("IMyInterface"), GuidAttribute);
        
        // The Value property of GuidAttribute returns a string. 
        System.Console.WriteLine( "IMyInterface Attribute: " + (GuidAttribute(IMyInterfaceAttribute)).Value );    

        // Using the string to create a guid.
        var myGuid1 : Guid = new Guid( (GuidAttribute(IMyInterfaceAttribute)).Value );
        // Using a byte array to create a guid.
        var myGuid2 : Guid = new Guid ( myGuid1.ToByteArray() );

        // Equals is overridden and so value comparison is done though references are different.
        if ( myGuid1.Equals( myGuid2 ) )
            System.Console.WriteLine( "myGuid1 equals myGuid2" );
        else
            System.Console.WriteLine( "myGuid1 not equals myGuid2" );

        // Equality operator can also be used to determine if two guids have same value.
        if ( myGuid1 == myGuid2 )
            System.Console.WriteLine( "myGuid1 == myGuid2" );
        else
            System.Console.WriteLine( "myGuid1 != myGuid2" );
    
        // CompareTo returns 0 if the guids have same value.
        if ( myGuid1.CompareTo( myGuid2 ) == 0 )
            System.Console.WriteLine( "myGuid1 compares to myGuid2" );
        else
            System.Console.WriteLine( "myGuid1 does not compare to myGuid2" );

        System.Console.ReadLine();

        //Output.
        //IMyInterface Attribute: F9168C5E-CEB2-4faa-B6BF-329BF39FA1E4
        //myGuid1 equals myGuid2
        //myGuid1 == myGuid2
        //myGuid1 compares to myGuid2
    }
}

MyTestClass.Main();

线程安全

此类型的任何公共静态（Visual Basic 中的 Shared）成员都是线程安全的，但不保证所有实例成员都是线程安全的。

平台

Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition

.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。

版本信息

.NET Framework

受以下版本支持：2.0、1.1、1.0

.NET Compact Framework

受以下版本支持：2.0、1.0

请参见

参考

Guid 成员
System 命名空间