C#

// Create the policy statement.
NamedPermissionSet namedPS = new NamedPermissionSet("FullTrust");
PolicyStatement ps = new PolicyStatement(namedPS);
ps.Attributes = PolicyStatementAttribute.Exclusive;
 
// Create the membership condition.
string url = "http://www.dummycorp.com";
UrlMembershipCondition condition = new UrlMembershipCondition(url);
 
// Create the code group.
UnionCodeGroup proplanner = new UnionCodeGroup(condition, ps);
proplanner.Name = "MyCodeGroup";
proplanner.Description = "Allows fully-trusted access to the URL.";
 
// Find the machine policy level.
PolicyLevel machine = null;
IEnumerator ie = SecurityManager.PolicyHierarchy();
while (ie.MoveNext())
  if (String.Compare(((PolicyLevel)ie.Current).Label, "Machine", true) == 0)
    machine = (PolicyLevel)ie.Current;
 
// If the machine policy level was not found, throw an exception.
if (machine == null)
  throw new InstallException("Unable to find the Machine policy level.");
 
// Enumerate the root code group children and
// determine if the Proplanner group already exists.
bool exists = false;
foreach (CodeGroup group in machine.RootCodeGroup.Children)
{
  if (proplanner.Equals(group))
  {
    exists = true;
    break;
  }
}
 
// If the code group doesn't exist, add it.
if (!exists)
{
  // Add our code group to the root code group.
  machine.RootCodeGroup.AddChild(proplanner);
  SecurityManager.SavePolicyLevel(machine);
}

StreamWriter sw = New StreamWriter(datapath + "\scheduler.txt");

Environment.CurrentDirectory = datapath;

namespace MyApplication
{
	[SecurityRole("MyAppClients")]
	public interface IMyInterface
	{
		string MyMethod(string s1, string s2);
	}

	/// <summary>
	/// Summary description for Class1.
	/// </summary>
	[ConstructionEnabled(true, Default="Server=(local);trusted connection=yes")]
	[Transaction(TransactionOption.Supported)]
	[ComponentAccessControl(true)]
	[SecurityRole("MyAppClients")]
	//[SecureMethod]
	public class MyClass: ServicedComponent, IMyInterface
	{
		private string connectionString = String.Empty;

		public MyClass()
		{
			//
			// TODO: Add constructor logic here
			//
		}
	
		protected override void Construct(string s)
		{
			this.connectionString = s;

			base.Construct(s);
		}
	
		#region IMyInterfaceimplementation

		public string MyMethod(string s1, string s2)
		{
			// TODO:  Add DataAccess.GetLogonToken implementation
			return "My String";
		}

		#endregion
	}

IMyInterface myInterface = new MyClass();

string aString = myInterface.MyMethod("s1", "s2"));

IMyInterface myInterface = new MyClass();
if(myInterface != null)
   string aString = myInterface.MyMethod("s1", "s2");