Create New Xml File And Update values of the attributs in that XMl File

Creating New XmlFile

XmlTextWriter xml_writer = new XmlTextWriter(Server.MapPath(path), null);
  xml_writer.WriteStartDocument();
  xml_writer.WriteRaw("");
  xml_writer.WriteStartElement("Login_Details");
  xml_writer.WriteEndElement();
  xml_writer.WriteEndDocument();
  xml_writer.Close();

For Updating Attributes Value OF Xml 

XmlDocument xml_Doc = new XmlDocument();

xml_Doc.Load(Server.MapPath(path));

   XmlNode xml_node = xml_Doc.SelectSingleNode("Login_Details");
   foreach (XmlNode node in xml_node)
  {
    if (node.Attributes[0].InnerText.ToString()=="Test")
  {
  node.Attributes[0].InnerText = "Text_Modified";
  }
  }
  xml_Doc.Save(Server.MapPath(path));

Coding for Checking User Authentication with XML and Create login Details as XML File

XML Files

Create Xml File then use the below code to access.

C# Codings

int i, j;

   
  string users_pass = string.Empty;
  string users_fail = string.Empty;
   
  XmlDocument xml_document = new XmlDocument();
  xml_document.Load(Server.MapPath("Login_Details.xml"));
  XmlNodeList node_list = xml_document.GetElementsByTagName("username");
  for ( i = 0; i < j =" 0;" user_name="node_list[i].ChildNodes[0].InnerText;" pass_word="node_list[i].ChildNodes[1].InnerText;" pass_count =" pass_count" pass_username =" user_name.ToString();" fail_count =" fail_count">= 1)
  {
   string date = System.DateTime.Now.ToShortDateString();
  string date_format = date.Replace('/', '-');
  string path = "Login_info_" + date_format.ToString() + ".XML";
  XmlDocument xml_doc = new XmlDocument();
  xml_doc.Load(Server.MapPath(path));
  XmlNode xml_sel = xml_doc.SelectSingleNode("Login_Details");
  XmlElement xml_ele = xml_doc.CreateElement("Login_Info");
  xml_ele.SetAttribute("user_login", pass_username.ToString());
  xml_sel.AppendChild(xml_ele);
   xml_ele.SetAttribute("login_time", System.DateTime.Now.ToString());
  xml_sel.AppendChild(xml_ele);
  xml_doc.Save(Server.MapPath(path));
  Response.Write("System pass :"+pass_username.ToString());
  pass_count = 0;
  }
  else
  {
  Response.Write("System Fails :"+pass_username.ToString());
  fail_count = 0;
  }

Creating Delegates Using C#.net

Creating Of Deletecates Events

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

namespace delegates
{
  ///

  /// Summary description for Delegates
  ///

  public class Delegates : System.Collections.ArrayList
  {
  public event System.EventHandler changed;

  protected virtual void Onchanged(System.EventArgs e)
  {
  if (changed != null)
  {
  changed(this, e);
  }
  }
  public override int Add(object value)
  {
  int i = base.Add(value);
  Onchanged(System.EventArgs.Empty);
  return i;

  }
  public Delegates()
  {

  //
  // TODO: Add constructor logic here
  //
  }
  }

}

Creation Of EventHander and Fucntions

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

///

/// Summary description for delegates_list
///

/// 
using delegates;
namespace delegates_list_pro
{
public class delegates_list
{
  private Delegates list1;
  public delegates_list(Delegates alist)
  {
  list1=alist;
  list1.changed+=new System.EventHandler(listadded);
   
  }
  private void listadded(object sender,EventArgs e)
  {
  System.Windows.Forms.MessageBox.Show("WELCOME");
  }
  public void Detach()
  {
  list1.changed-=new System.EventHandler(listadded);
  list1=null;
  }



 public delegates_list()
 {
  //
  // TODO: Add constructor logic here
  //
 }
}
}

Calling Detlegates and its event handlers from the main program

using delegates;
using delegates_list_pro;

Delegates dele = new Delegates();
delegates_list listener = new delegates_list(dele);
dele.Add("Welcome");
dele.Clear();
listener.Detach();

Coding for Creating a Window Snap Shot Using C#.net

Add the reference of system.windows.form by address reference option 

using System.Drawing;
using System.IO;
using System.Text;
using System.Windows.Forms;

//file name is created based on a time
File_name.Text = System.DateTime.Now.ToShortTimeString();
  string file_name = File_name.Text.Replace(':', '-');
  Bitmap image = new Bitmap(System.Windows.Forms.Screen.PrimaryScreen.Bounds.Width, System.Windows.Forms.Screen.PrimaryScreen.Bounds.Height, System.Drawing.Imaging.PixelFormat.Format32bppArgb);
  System.Drawing.Graphics graphics = System.Drawing.Graphics.FromImage(image);  graphics.CopyFromScreen(System.Windows.Forms.Screen.PrimaryScreen.Bounds.X, System.Windows.Forms.Screen.PrimaryScreen.Bounds.Y, 0, 0, System.Windows.Forms.Screen.PrimaryScreen.Bounds.Size, System.Drawing.CopyPixelOperation.SourceCopy);
 image.Save("C:/temp/" + file_name.ToString()+".jpg");
Note:
IF You want to take a snap shot for particualr timer interval, just added a meta tag inside head tag
meta http-equiv="refresh" content="60"
60 refers the page refreshing time in a seconds..