C # windows Calculator

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

Namespace comput
{
/// <Summary>
/// This is a simple implementation of a calculator.
/// </Summary>

Public class Form1: System. Windows. Forms. Form
{
# Region control declaration

Private System. Windows. Forms. TextBox txtShow;
Private System. Windows. Forms. GroupBox groupBox1;
Private System. Windows. Forms. Button btn_rev;
Private System. Windows. Forms. Button btn_dot;
Private System. Windows. Forms. Button btn_add;
Private System. Windows. Forms. Button btn_equ;
Private System. Windows. Forms. Button btn_sign;
Private System. Windows. Forms. Button btn_sub;
Private System. Windows. Forms. Button btn_mul;
Private System. Windows. Forms. Button btn_0;
Private System. Windows. Forms. Button btn_3;
Private System. Windows. Forms. Button btn_2;
Private System. Windows. Forms. Button btn_1;
Private System. Windows. Forms. Button btn_6;
Private System. Windows. Forms. Button btn_5;
Private System. Windows. Forms. Button btn_4;
Private System. Windows. Forms. Button btn_sqrt;
Private System. Windows. Forms. Button btn_div;
Private System. Windows. Forms. Button btn_7;
Private System. Windows. Forms. Button btn_8;
Private System. Windows. Forms. Button btn_9;
Private System. Windows. Forms. MainMenu mainMenu1;
Private System. Windows. Forms. MenuItem menuItem1;
Private System. Windows. Forms. Button btn_sqr;
Private System. Windows. Forms. MenuItem menuItem2;
Private System. Windows. Forms. MenuItem menuItem3;
Private System. Windows. Forms. MenuItem menuItem4;
Private System. Windows. Forms. MenuItem menuItem5;
Private System. Windows. Forms. MenuItem menuItem6;
Private System. Windows. Forms. Button c;
Private System. Windows. Forms. Button ce;
Private System. Windows. Forms. MenuItem menuItem8;
Private System. Windows. Forms. MenuItem menuItem9;
Private System. Windows. Forms. MenuItem menuItem10;
/// <Summary>
/// Required designer variables.
/// </Summary>
Private System. ComponentModel. Container components = null;


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

//
// TODO: add Any constructor code after InitializeComponent calls
//
}



/// <Summary>
/// Clear all resources in use.
/// </Summary>
Protected override void Dispose (bool disposing)
{
If (disposing)
{
If (components! = Null)
{
Components. Dispose ();
}
}
Base. Dispose (disposing );
}
# Endregion

# Region control attributes method Windows Form Designer generated code
/// <Summary>
/// The designer supports the required methods-do not use the code editor to modify
/// Content of this method.
/// </Summary>
Private void InitializeComponent ()
{
System. Resources. ResourceManager resources = new System. Resources. ResourceManager (typeof (Form1 ));
This.txt Show = new System. Windows. Forms. TextBox ();
This. groupBox1 = new System. Windows. Forms. GroupBox ();
This. c = new System. Windows. Forms. Button ();
This. ce = new System. Windows. Forms. Button ();
This. btn_rev = new System. Windows. Forms. Button ();
This. btn_dot = new System. Windows. Forms. Bu