using System;
using System.Windows.Forms;
using CrystalDecisions.CrystalReports.Engine;
using CrystalDecisions.Shared;
using System.Web.Mail;

namespace WindowsApplication1
{
    public partial class Form1 : Form
    {
        ReportDocument cryRpt;
        string pdfFile = "c:\\csharp.net-informations.pdf";

        public Form1()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            cryRpt = new ReportDocument();
            cryRpt.Load(PUT CRYSTAL REPORT PATH HERE\\CrystalReport1.rpt");
            crystalReportViewer1.ReportSource = cryRpt;
            crystalReportViewer1.Refresh(); 
        }

        private void button2_Click(object sender, EventArgs e)
        {
            try
            {
                ExportOptions CrExportOptions ;
                DiskFileDestinationOptions CrDiskFileDestinationOptions = new DiskFileDestinationOptions();
                PdfRtfWordFormatOptions CrFormatTypeOptions = new PdfRtfWordFormatOptions();
                CrDiskFileDestinationOptions.DiskFileName = pdfFile;
                CrExportOptions = cryRpt.ExportOptions;
                CrExportOptions.ExportDestinationType = ExportDestinationType.DiskFile;
                CrExportOptions.ExportFormatType = ExportFormatType.PortableDocFormat;
                CrExportOptions.DestinationOptions = CrDiskFileDestinationOptions;
                CrExportOptions.FormatOptions = CrFormatTypeOptions;
                cryRpt.Export();

                sendmail();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.ToString());
            }
        }

        private void sendmail()
        {
            try {
                SmtpMail.SmtpServer.Insert(0, "your hostname");
                MailMessage Msg = new MailMessage();
                Msg.To = "to address here";
                Msg.From = "from address here";
                Msg.Subject = "Crystal Report Attachment ";
                Msg.Body = "Crystal Report Attachment ";
                Msg.Attachments.Add(new MailAttachment(pdfFile));
                System.Web.Mail.SmtpMail.Send(Msg);
            } 
            catch (Exception ex) { 
                MessageBox.Show (ex.ToString()); 
            }         
        }
    }
}

At its simplest, an object holds a single value. At its most complex, it holds references to many other objects. The .NET Framework provides collections—these include List and Dictionary. They are often useful.

List

First, the List type provides an efficient and dynamically-allocated array. It does not provide fast lookup in the general case—the Dictionary is better for this. List is excellent when used in loops.
List

Program that uses List type [C#]

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
 // Use the List type.
 List<string> list = new List<string>();
 list.Add("cat");
 list.Add("dog");

 foreach (string element in list)
 {
     Console.WriteLine(element);
 }
    }
}

Output

cat
dog

Dictionary

The Dictionary type in the base class library is an important one. It is an implementation of a hashtable, which is an extremely efficient way to store keys for lookup. The Dictionary in .NET is well-designed.
Dictionary

Program that uses Dictionary [C#]

using System;
using System.Collections.Generic;

class Program
{
    static void Main()
    {
 // Use the dictionary.
 Dictionary<string, int> dict = new Dictionary<string, int>();
 dict.Add("cat", 1);
 dict.Add("dog", 4);

 Console.WriteLine(dict["cat"]);
 Console.WriteLine(dict["dog"]);
    }
}

Output

1
4

Generic Class

ArrayList

Next, the ArrayList is a collection found in System.Collections and it can store objects of any derived type. You don't need to worry about the type of the elements, at least until you need to use them.
ArrayList

Program that uses System.Collections [C#]

using System;
using System.Collections;

class Program
{
    static void Main()
    {
 ArrayList list = new ArrayList();
 list.Add("cat");
 list.Add(2);
 list.Add(false);

 foreach (var element in list)
 {
     Console.WriteLine(element);
 }
    }
}

Output

cat
2
False

Hashtable

To continue, the Hashtable is a lookup data structure that uses a hash code to find elements quickly. The newer Dictionary collection is usually more appropriate for programs when available.
Hashtable

Program that uses Hashtable [C#]

using System;
using System.Collections;

class Program
{
    static void Main()
    {
 Hashtable table = new Hashtable();
 table["one"] = 1;
 table["two"] = 2;

 // ... Print value at key.
 Console.WriteLine(table["one"]);
    }
}

Output

1

Lists

Lists are linear—one element is stored after the other. The List generic type is often the best implementation available for its purpose on the .NET Framework. There are other versions of lists.
LinkedList SortedList ReadOnlyCollection Capacity

Tables

There are many versions of lookup data structures other than the Hashtable and Dictionary in the .NET Framework. Usually, a Dictionary is the best option—but sometimes custom features are needed.

Introduction:

Here I will explain what windows service is, uses of windows service and how to create windows service in c#.

Description:

/// <summary> /// The main entry point for the application. /// </summary> static void Main() { ServiceBase[] ServicesToRun; ServicesToRun = new ServiceBase[] { new ScheduledService() }; ServiceBase.Run(ServicesToRun); }

using System.IO; using System.Timers;

protected override void OnStart(string[] args) { } protected override void OnStop() { }

//Initialize the timer Timer timer = new Timer(); public ScheduledService() { InitializeComponent(); } //This method is used to raise event during start of service protected override void OnStart(string[] args) { //add this line to text file during start of service TraceService("start service"); //handle Elapsed event timer.Elapsed += new ElapsedEventHandler(OnElapsedTime); //This statement is used to set interval to 1 minute (= 60,000 milliseconds) timer.Interval = 60000; //enabling the timer timer.Enabled = true; } //This method is used to stop the service protected override void OnStop() { timer.Enabled = false; TraceService("stopping service"); } private void OnElapsedTime(object source, ElapsedEventArgs e) { TraceService("Another entry at "+DateTime.Now); } private void TraceService(string content) { //set up a filestream FileStream fs = new FileStream(@"d:\ScheduledService.txt",FileMode.OpenOrCreate, FileAccess.Write); //set up a streamwriter for adding text StreamWriter sw = new StreamWriter(fs); //find the end of the underlying filestream sw.BaseStream.Seek(0, SeekOrigin.End); //add the text sw.WriteLine(content); //add the text to the underlying filestream sw.Flush(); //close the writer sw.Close(); }

Now the service is installed. To start and stop the service, go to Control Panel --> Administrative Tools --> Services.  Right click the service and select Start. 

Now the service is started, and you will be able to see entries in the log file we defined in the code.

Now open the log file in your folder that Output of the file like this

CTRL + M + O will collapse all. CTRL + M + L will expand all. CTRL + M + P will expand all and disable outlining. CTRL + M + M will collapse/expand the current section. These options are also in the context menu under Outlining.

 void clear()
    {
        foreach (Control c in form1.Controls)       //This loop takes all controls from the form1
        {
            //Clear all textbox values
            if (c is TextBox)
                ((TextBox)c).Text = "";

            //clear all check boxes
            if (c is CheckBox)
                ((CheckBox)c).Checked = false;

            //Clear all radio buttons
            if (c is RadioButton)
                ((RadioButton)c).Checked = false;
        }
    }