using System; using System.Drawing; using System.Collections; using System.ComponentModel; using System.Windows.Forms; using System.Data; using System.Security; using System.IO; using System.Security.Permissions; public class MainClass { public static void Main(){ PermissionSet ps = new PermissionSet(System.Security.Permissions.PermissionState.None); ps.AddPermission(new FileIOPermission(FileIOPermissionAccess.Read |FileIOPermissionAccess.Write | FileIOPermissionAccess.Append,"c: emp emp.txt")); ps.Deny(); //ps.Assert(); FileStream fs = new FileStream(@"c: emp emp.txt",FileMode.OpenOrCreate, FileAccess.Write); StreamWriter m_streamWriter = new StreamWriter(fs); m_streamWriter.BaseStream.Seek(0, SeekOrigin.End); m_streamWriter.Write("Test"); } }