GacMembershipCondition Class

Definition

Namespace:

System.Security.Policy

Assembly:

System.Security.Permissions.dll

Source:

GacMembershipCondition.cs

Determines whether an assembly belongs to a code group by testing its global assembly cache membership. This class cannot be inherited.

C#

public sealed class GacMembershipCondition : System.Security.ISecurityEncodable, System.Security.Policy.IMembershipCondition

Inheritance

Object

GacMembershipCondition

Implements

ISecurityEncodable ISecurityPolicyEncodable IMembershipCondition

Examples

The following example demonstrates the use of the GacMembershipCondition class.

C#

using System;
using System.Security; 
using System.Security.Policy; 
using System.Collections;

public class GacMembershipConditionDemo
{
    // Demonstrate the Copy method, which creates an identical
    // copy of the current permission.
    private bool CopyDemo()
    {
        Console.WriteLine(
            "************************************************************");
        GacMembershipCondition Gac1 = new GacMembershipCondition();
        Console.WriteLine("Original membership condition = ");
        Console.WriteLine(Gac1.ToXml().ToString());
        try
        {
            IMembershipCondition membershipCondition = Gac1.Copy();
            Console.WriteLine("Result of Copy = ");
            Console.WriteLine(
                ((GacMembershipCondition)membershipCondition).ToXml().ToString()
                );
        }
        catch (Exception e)
        {
            Console.WriteLine("Copy failed : " + Gac1.ToString() + e);
            return false;
        }

        return true;
    }
    // Demonstrate the Check method, which determines whether the specified 
    // evidence satisfies the membership condition.
    private bool CheckDemo()
    {
        Console.WriteLine(
            "************************************************************");
        GacMembershipCondition Gac1 = new GacMembershipCondition();
        GacInstalled myGac = new GacInstalled();
        try
        {
            Object [] hostEvidence = {myGac};
            Object [] assemblyEvidence = {};

            Evidence myEvidence = new Evidence(hostEvidence,assemblyEvidence);
            bool retCode = Gac1.Check(myEvidence);
            Console.WriteLine("Result of Check = " + retCode.ToString() + "\n");
        }
        catch (Exception e)
        {
            Console.WriteLine("Check failed : " + Gac1.ToString() + e);
            return false;
        }

        return true;
    }

    // Demonstrate the GetHashCode method, which returns a hash code
    // for the specified membership condition.
    private bool GetHashCodeDemo()
    {
        Console.WriteLine(
            "************************************************************");
        GacMembershipCondition Gac1 = new GacMembershipCondition();
        try
        {
            Console.WriteLine(
                "Result of GetHashCode for a GacMembershipCondition = " + 
                Gac1.GetHashCode().ToString() + "\n");
        }
        catch (Exception e)
        {
            Console.WriteLine("GetHashCode failed : " + Gac1.ToString() + e);
            return false;
        }

        return true;
    }

    // Demonstrate the ToXml and FromXml methods, including the overloads.
    // ToXml creates an XML encoding of the membership condition and its 
    // current state; FromXml reconstructs a membership condition with the 
    // specified state from the XML encoding.
    private bool ToFromXmlDemo()
    {
        Console.WriteLine(
            "************************************************************");
        try
        {
            GacMembershipCondition Gac1 = new GacMembershipCondition();
            GacMembershipCondition Gac2 = new GacMembershipCondition();

            // Roundtrip a GacMembershipCondition to and from an XML encoding.
            Gac2.FromXml(Gac1.ToXml());
            bool result = Gac2.Equals(Gac1);
            if (result)
            {
                Console.WriteLine(
                    "Result of ToXml() = " + Gac2.ToXml().ToString());
                Console.WriteLine(
                    "Result of ToFromXml roundtrip = " + Gac2.ToString());
            }
            else
            {
                Console.WriteLine(Gac2.ToString());
                Console.WriteLine(Gac1.ToString());
                return false;
            }

            GacMembershipCondition Gac3 = new GacMembershipCondition();
            GacMembershipCondition Gac4 = new GacMembershipCondition();
            IEnumerator policyEnumerator = SecurityManager.PolicyHierarchy();
            while (policyEnumerator.MoveNext())
            {
                PolicyLevel currentLevel = 
                    (PolicyLevel)policyEnumerator.Current;
                if (currentLevel.Label == "Machine")
                {
                    Console.WriteLine("Result of ToXml(level) = " + 
                        Gac3.ToXml(currentLevel));
                    Gac4.FromXml(Gac3.ToXml(), currentLevel);
                    Console.WriteLine("Result of FromXml(element, level) = " + 
                        Gac4.ToString());
                }
            }
        }
        catch (Exception e)
        {
            Console.WriteLine("ToFromXml failed. " + e);
            return false;
        }

        return true;
    }

    // Invoke all demos.
    public bool RunDemo()
    {

        bool returnCode =true;
        bool tempReturnCode;

        // Call the Copy demo.
        if (tempReturnCode = CopyDemo())
            Console.Out.WriteLine("Copy demo completed successfully.");
        else 
            Console.Out.WriteLine("Copy demo failed.");

        returnCode = tempReturnCode && returnCode;

        // Call the Check demo.
        if (tempReturnCode = CheckDemo())
            Console.Out.WriteLine("Check demo completed successfully.");
        else 
            Console.Out.WriteLine("Check demo failed.");

        returnCode = tempReturnCode && returnCode;

        // Call the GetHashCode demo.
        if (tempReturnCode = GetHashCodeDemo())
            Console.Out.WriteLine("GetHashCode demo completed successfully.");
        else 
            Console.Out.WriteLine("GetHashCode demo failed.");

        returnCode = tempReturnCode && returnCode;

        // Call the ToFromXml demo.	
        if (tempReturnCode = ToFromXmlDemo())
            Console.Out.WriteLine("ToFromXml demo completed successfully.");
        else 
            Console.Out.WriteLine("ToFromXml demo failed.");

        returnCode = tempReturnCode && returnCode;
        return (returnCode);	
    }

    // Test harness.
    public static void Main(String[] args)
    {
        try
        {
            GacMembershipConditionDemo testcase = 
                new GacMembershipConditionDemo();
            bool returnCode = testcase.RunDemo();
            if (returnCode)
            {
                Console.Out.WriteLine(
                    "The GacMembershipCondition demo completed successfully.");
                Console.Out.WriteLine("Press the Enter key to exit.");
                string consoleInput = Console.ReadLine();
                System.Environment.ExitCode = 100;
            }
            else
            {
                Console.Out.WriteLine("The GacMembershipCondition demo failed.");
                Console.Out.WriteLine("Press the ENTER key to exit.");
                string consoleInput = Console.ReadLine();
                System.Environment.ExitCode = 101;
            }
        }
        catch (Exception e)
        {
            Console.Out.WriteLine("The GacIdentityPermission demo failed.");
            Console.WriteLine(e.ToString());
            Console.Out.WriteLine("Press the Enter key to exit.");
            string consoleInput = Console.ReadLine();
            System.Environment.ExitCode = 101;
        }
    }
}

Remarks

All assemblies installed in the global assembly cache are granted the FullTrust permission set.

Constructors

GacMembershipCondition()

Initializes a new instance of the GacMembershipCondition class.

Methods

Check(Evidence)	Indicates whether the specified evidence satisfies the membership condition.
Copy()	Creates an equivalent copy of the membership condition.
Equals(Object)	Indicates whether the current object is equivalent to the specified object.
FromXml(SecurityElement, PolicyLevel)	Uses the specified XML encoding to reconstruct a security object, using the specified policy level context.
FromXml(SecurityElement)	Uses the specified XML encoding to reconstruct a security object.
GetHashCode()	Gets a hash code for the current membership condition.
ToString()	Returns a string representation of the membership condition.
ToXml()	Creates an XML encoding of the security object and its current state.
ToXml(PolicyLevel)	Creates an XML encoding of the security object and its current state, using the specified policy level context.

Applies to