AssemblyIdentity

System.Security.Policy

Overview Syntax Constructors Properties Methods Remarks Examples

Overview

Represents the identity of a code assembly. The AssemblyIdentity class is used to identify code assemblies for policy resolution. It contains information such as the culture, version, and processor architecture of an assembly. This class cannot be inherited.

The AssemblyIdentity class provides a way to define and compare the identities of assemblies. This is crucial for security policy, as it allows the system to determine which policies apply to a given assembly.

Syntax

[SerializableAttribute]
public sealed class AssemblyIdentity : System.Security.Policy.EvidenceBase, System.Security.Principal.IIdentity

Constructors

AssemblyIdentity()
Initializes a new instance of the AssemblyIdentity class with default values.
AssemblyIdentity(string name, string version, string culture, string publicKey, string publicKeyToken)
Initializes a new instance of the AssemblyIdentity class with the specified assembly information.

Properties

Culture
Gets the culture of the assembly.
Name
Gets the name of the assembly.
ProcessorArchitecture
Gets the processor architecture of the assembly.
PublicKey
Gets the public key of the assembly.
PublicKeyToken
Gets the public key token of the assembly.
Version
Gets the version of the assembly.

Methods

Clone()
Creates a new object that is a copy of the current instance. (Inherited from Object)
Equals(Object obj)
Determines whether the specified object is equal to the current object.
GetHashCode()
Serves as the default hash function.
GetType()
Gets the Type of the current instance.
ToString()
Returns a string that represents the current object.

Remarks

The AssemblyIdentity class is an EvidenceBase, meaning it can be used as evidence for code access security (CAS) policy. When an assembly is loaded, the system can extract various pieces of evidence about it, including its identity. This evidence is then used to determine the permissions granted to the assembly.

The properties of AssemblyIdentity allow for precise identification of an assembly. The PublicKeyToken is often used as a strong identifier, as it is a hash of the public key and is typically much shorter.

When comparing AssemblyIdentity objects, the equality check considers all relevant properties. For example, two AssemblyIdentity objects are considered equal if they have the same name, version, culture, and public key token.

Examples

The following example demonstrates how to create and use an AssemblyIdentity object.

using System;
using System.Security.Policy;

public class AssemblyIdentityExample
{
    public static void Main(string[] args)
    {
        // Create an AssemblyIdentity with specific details
        AssemblyIdentity identity1 = new AssemblyIdentity(
            "MyAssembly",
            "1.0.0.0",
            "en-US",
            "0000000000000000", // Example public key token
            "0000000000000000"  // Example public key token
        );

        Console.WriteLine($"Assembly Name: {identity1.Name}");
        Console.WriteLine($"Version: {identity1.Version}");
        Console.WriteLine($"Culture: {identity1.Culture}");
        Console.WriteLine($"Public Key Token: {identity1.PublicKeyToken}");

        // Create another AssemblyIdentity for comparison
        AssemblyIdentity identity2 = new AssemblyIdentity(
            "MyAssembly",
            "1.0.0.0",
            "en-US",
            "0000000000000000",
            "0000000000000000"
        );

        // Compare identities
        if (identity1.Equals(identity2))
        {
            Console.WriteLine("\nIdentity 1 is equal to Identity 2.");
        }
        else
        {
            Console.WriteLine("\nIdentity 1 is not equal to Identity 2.");
        }

        // Get the hash code
        Console.WriteLine($"Hash code for identity1: {identity1.GetHashCode()}");
    }
}