C Sharp Form Uygulamalar Faktöriyel Hesaplama

using System;
using System.Drawing;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace Faktöriyel
{
 /// 
 /// Summary description for Form1.
 /// 
 public class Form1 : System.Windows.Forms.Form
 {
  private System.Windows.Forms.TextBox txtSonuc;
        private System.Windows.Forms.Button btnFaktoriyelHesaplama;
        private System.Windows.Forms.Label lblSayi;
        private System.Windows.Forms.Button txtFaktoriyelSonuc;
        private System.Windows.Forms.Label lblSonuc;
  /// 
  /// Required designer variable.
  /// 
  private System.ComponentModel.Container components = null;

  public Form1()
  {
   //
   // Required for Windows Form Designer support
   //
   InitializeComponent();

   //
   // TODO: Add any constructor code after InitializeComponent call
   //
  }

  /// 
  /// Clean up any resources being used.
  /// 
  protected override **** Dispose( bool disposing )
  {
   if( disposing )
   {
    if (components != null) 
    {
     components.Dispose();
    }
   }
   base.Dispose( disposing );
  }

  #region Windows Form Designer generated code
  /// 
  /// Required method for Designer support - do not modify
  /// the contents of this method with the code editor.
  /// 
  private **** InitializeComponent()
  {
            System.ComponentModel.ComponentResourceManager resources = new System.ComponentModel.ComponentResourceManager(typeof(Form1));
            this.txtSonuc = new System.Windows.Forms.TextBox();
            this.btnFaktoriyelHesaplama = new System.Windows.Forms.Button();
            this.lblSayi = new System.Windows.Forms.Label();
            this.txtFaktoriyelSonuc = new System.Windows.Forms.Button();
            this.lblSonuc = new System.Windows.Forms.Label();
            this.SuspendLayout();
            // 
            // txtSonuc
            // 
            this.txtSonuc.BorderStyle = System.Windows.Forms.BorderStyle.FixedSingle;
            this.txtSonuc.******** = new System.Drawing.Point(93, 64);
            this.txtSonuc.Name = "txtSonuc";
            this.txtSonuc.Size = new System.Drawing.Size(187, 20);
            this.txtSonuc.TabIndex = 0;
            // 
            // btnFaktoriyelHesaplama
            // 
            this.btnFaktoriyelHesaplama.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
            this.btnFaktoriyelHesaplama.******** = new System.Drawing.Point(93, 90);
            this.btnFaktoriyelHesaplama.Name = "btnFaktoriyelHesaplama";
            this.btnFaktoriyelHesaplama.Size = new System.Drawing.Size(187, 23);
            this.btnFaktoriyelHesaplama.TabIndex = 1;
            this.btnFaktoriyelHesaplama.Text = "Hesapla";
            this.btnFaktoriyelHesaplama.Click += new System.EventHandler(this.btnFaktoriyelHesapla_Click);
            // 
            // label2
            // 
            this.lblSayi.AutoSize = true;
            this.lblSayi.Font = new System.Drawing.Font("Arial", 12F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((byte)(162)));
            this.lblSayi.ForeColor = System.Drawing.Color.Firebrick;
            this.lblSayi.******** = new System.Drawing.Point(11, 123);
            this.lblSayi.Name = "label2";
            this.lblSayi.Size = new System.Drawing.Size(76, 19);
            this.lblSayi.TabIndex = 3;
            this.lblSayi.Text = "Sonuç = ";
            // 
            // txtFaktoriyelSonuc
            // 
            this.txtFaktoriyelSonuc.FlatAppearance.MouseDownBackColor = System.Drawing.Color.FromArgb(((int)(((byte)(255)))), ((int)(((byte)(128)))), ((int)(((byte)(128)))));
            this.txtFaktoriyelSonuc.FlatAppearance.MouseOverBackColor = System.Drawing.Color.FromArgb(((int)(((byte)(255)))), ((int)(((byte)(128)))), ((int)(((byte)(128)))));
            this.txtFaktoriyelSonuc.FlatStyle = System.Windows.Forms.FlatStyle.Flat;
            this.txtFaktoriyelSonuc.******** = new System.Drawing.Point(93, 119);
            this.txtFaktoriyelSonuc.Name = "txtFaktoriyelSonuc";
            this.txtFaktoriyelSonuc.Size = new System.Drawing.Size(187, 23);
            this.txtFaktoriyelSonuc.TabIndex = 4;
            this.txtFaktoriyelSonuc.Text = "0";
            // 
            // label1
            // 
            this.lblSonuc.AutoSize = true;
            this.lblSonuc.Font = new System.Drawing.Font("Arial", 12F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((byte)(162)));
            this.lblSonuc.ForeColor = System.Drawing.Color.Firebrick;
            this.lblSonuc.******** = new System.Drawing.Point(12, 65);
            this.lblSonuc.Name = "label1";
            this.lblSonuc.Size = new System.Drawing.Size(52, 19);
            this.lblSonuc.TabIndex = 5;
            this.lblSonuc.Text = "Sayı :";
            // 
            // Form1
            // 
            this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);
            this.BackColor = System.Drawing.Color.FromArgb(((int)(((byte)(255)))), ((int)(((byte)(128)))), ((int)(((byte)(128)))));
            this.ClientSize = new System.Drawing.Size(292, 266);
            this.Controls.Add(this.lblSonuc);
            this.Controls.Add(this.txtFaktoriyelSonuc);
            this.Controls.Add(this.lblSayi);
            this.Controls.Add(this.btnFaktoriyelHesaplama);
            this.Controls.Add(this.txtSonuc);
            this.Icon = ((System.Drawing.Icon)(resources.GetObject("$this.Icon")));
            this.Name = "Form1";
            this.Text = "Faktoriyel Hesaplama";
            this.ResumeLayout(false);
            this.PerformLayout();

  }
  #endregion

  /// 
  /// The main entry point for the application.
  /// 
  [STAThread]
  static **** Main() 
  {
   Application.Run(new Form1());
  }

        private **** btnFaktoriyelHesapla_Click(object sender, System.EventArgs e)
        {

            try
            {
                double faktoriyelSonuc, counter, girilenSayi;

                //girilen değeri double tipine çevirelim. Eğer girilen değer double tipine 
                //çevrilemezse işlem catch bloğuna atlayıp programdan çıkacak

                girilenSayi = Convert.ToDouble(txtSonuc.Text);

                counter = 1;

                faktoriyelSonuc = 1;

                //1 den başlayarak girilen sayıya kadar bütün sayıların çarpımını hesaplayarak 
                //girilen sayının faktoriyelini hesaplayalım

                while (counter <= girilenSayi)
                {
                    faktoriyelSonuc = faktoriyelSonuc * counter;

                    counter = counter + 1;
                }

                //Hesaplan faktoriyel değerini sonuç kutusuna yazdıralım

                txtFaktoriyelSonuc.Text = Convert.ToString(faktoriyelSonuc);
            }
            catch (Exception)
            {
                MessageBox.Show("Bir Sayı girmelisiniz...", "Hata", MessageBoxButtons.OK, MessageBoxIcon.Error);
            }


        }
 }
}