C#

static void Serialize() <br />
		{<br />
			// Create a hashtable of values that will eventually be serialized.<br />
			Hashtable addresses = new Hashtable();<br />
			addresses.Add("Jeff", "123 Main Street, Redmond, WA 98052");<br />
			addresses.Add("Fred", "987 Pine Road, Phila., PA 19116");<br />
			addresses.Add("Mary", "PO Box 112233, Palo Alto, CA 94301");<br />
<br />
			// To serialize the hashtable and its key/value pairs,  <br />
			// you must first open a stream for writing. <br />
			// In this case, use a file stream.<br />
			FileStream fs = new FileStream("DataFile.dat", FileMode.Create);<br />
<br />
			// Construct a BinaryFormatter and use it to serialize the data to the stream.<br />
			BinaryFormatter formatter = new BinaryFormatter();<br />
			try <br />
			{<br />
				formatter.Serialize(fs, addresses);<br />
			}<br />
			catch (SerializationException e) <br />
			{<br />
				Console.WriteLine("Failed to serialize. Reason: " + e.Message);<br />
				throw;<br />
			}<br />
			finally <br />
			{<br />
				fs.Close();<br />
			}<br />
		}<br />
<br />
   <br />
		static void Deserialize() <br />
		{<br />
			// Declare the hashtable reference.<br />
			Hashtable addresses  = null;<br />
<br />
			// Open the file containing the data that you want to deserialize.<br />
			FileStream fs = new FileStream("DataFile.dat", FileMode.Open);<br />
			try <br />
			{<br />
				BinaryFormatter formatter = new BinaryFormatter();<br />
<br />
				// Deserialize the hashtable from the file and <br />
				// assign the reference to the local variable.<br />
				addresses = (Hashtable) formatter.Deserialize(fs);<br />
			}<br />
			catch (SerializationException e) <br />
			{<br />
				Console.WriteLine("Failed to deserialize. Reason: " + e.Message);<br />
				throw;<br />
			}<br />
			finally <br />
			{<br />
				fs.Close();<br />
			}<br />
<br />
			// To prove that the table deserialized correctly, <br />
			// display the key/value pairs.<br />
			foreach (DictionaryEntry de in addresses) <br />
			{<br />
				Console.WriteLine("{0} lives at {1}.", de.Key, de.Value);<br />
			}<br />
		}

using System;
using System.Windows.Forms;
public class MaskedTextBox : TextBox
{
	private string mask;
	public string Mask
	{
		get
		{
			return mask;
		}
		set
		{
			mask = value;
			this.Text = "";
		}
	}

Protected override void OnKeyPress(KeyPressEventArgs e)
	{
if (Mask != "")
{
e.Handled = true;
string newText = this.Text;
bool finished = false;
for (int i = this.SelectionStart; i < mask.Length; i++)
{
	switch (mask[i].ToString())
	{
	case "#" :
	   if (Char.IsDigit(e.KeyChar) )
	   {
	      if(this.TextLength<mask.Length)
	      {
	        newText += e.KeyChar.ToString();
	        finished = true;
	        break;
	      }
             else
	      {
	   newText=newText.Remove(i,this.SelectionLength);
	   newText=newText.Insert(i,e.KeyChar.ToString());
           finished = true;
	   break;
	       }
	}
	else
	{
	// Invalid entry; exit and don't change the text.
	return;
	}
	default :
	// Insert the mask character.
	newText += mask[i];
	break;
	}
	if (finished)
	{ break; }
	}
	// Update the text.
	this.Text = newText;
	this.SelectionStart = this.Text.Length;
         }
	}

	protected override void OnKeyDown(KeyEventArgs e)
	{
		// Stop special characters.
		e.Handled = true;
	}
}

maskTextBox.Mask = "$###,###";

<br />
with<pre><code><br />
if(this.TextLength<mask.Length)

<?xml version="1.0"?><br />
<!--Mohamed's Address Book - WRITING XML IN VB.NET--><br />
<!--AUTHOR - Mohamed Magdy--><br />
<phonebook><br />
    <contact><br />
        <firstname>A</firstname><br />
        <lastname>A</lastname><br />
        <phonenum>A</phonenum><br />
        <titel>A</titel><br />
        <nickname>A</nickname><br />
        <country /><br />
        <city>A</city><br />
        <address>A</address><br />
        <zipcode>A</zipcode><br />
        <job>A</job><br />
        <mail>A</mail><br />
        <site>A</site><br />
    </contact><br />
</phonebook>

<br />
string buff;<br />
int test = 450000;<br />
buff = test.ToString("###,###");<br />
test = 450000000;<br />
buff = test.ToString("###,###");<br />