Calculator program using C#

Calculator program using C#

using System;

using System.Windows.Forms;

using System.Drawing;

public class win:Form {

          Button[] b = new Button[10];

          Button bDot,bPlus,bSub,bMul,bDiv,bEqu,bClr;

          Panel panCalc;

          TextBox txtCalc;

         

          Double dblAcc;

          Double dblSec;

          bool blnClear,blnFrstOpen;

          String strOper;

         

          public win() {

             try {

                   this.Text="Calculator";

                   panCalc=new Panel();

                   txtCalc = new TextBox();

                   txtCalc.Location = new Point(10,10);

                   txtCalc.Size=new Size(150,10);

                   txtCalc.ReadOnly=true;

                   txtCalc.RightToLeft=RightToLeft.Yes;

                   panCalc.Size=new Size(200,200);

                   panCalc.BackColor=Color.Aqua;

                   panCalc.Controls.Add(txtCalc);

                   addButtons(panCalc);

                   this.Size=new Size(200,225);

                   this.Controls.Add(panCalc);

                  

                   dblAcc=0;

                   dblSec=0;

                   blnFrstOpen=true;

                   blnClear=false;

                   strOper=new String('=',1);

              }

              catch (Exception e) {

                   Console.WriteLine("error ......  " + e.StackTrace);

              }

          }

         

          private void addButtons(Panel p) {

                   for (int i=0;i<=9;i++) {

                             b[i]=new Button();

                             b[i].Text=Convert.ToString(i);

                             b[i].Size=new Size(25,25);

                             b[i].BackColor=Color.White;

                             b[i].Click+=new EventHandler(btn_clk);

                             p.Controls.Add(b[i]);    

                   }

                   b[0].Location=new Point(10,160);

                   b[1].Location=new Point(10,120);

                   b[4].Location=new Point(10,80);

                   b[7].Location=new Point(10,40);

                  

                   b[2].Location=new Point(50,120);

                   b[5].Location=new Point(50,80);

                   b[8].Location=new Point(50,40);

                  

                   b[3].Location=new Point(90,120);

                   b[6].Location=new Point(90,80);

                   b[9].Location=new Point(90,40);

                  

                   bDot=new Button();

                   bDot.Size=new Size(25,25);

                   bDot.Location=new Point(50,160);

                   bDot.BackColor=Color.White;

                   bDot.Text=".";

                   bDot.Click+=new EventHandler(btn_clk);

                  

                   bPlus=new Button();

                   bPlus.Size=new Size(25,25);

                   bPlus.Location=new Point(130,160);

                   bPlus.BackColor=Color.White;

                   bPlus.Text="+";

                   bPlus.Click+=new EventHandler(btn_Oper);

                  

                   bSub=new Button();

                   bSub.Size=new Size(25,25);

                   bSub.Location=new Point(130,120);

                   bSub.BackColor=Color.White;

                   bSub.Text="-";

                   bSub.Click+=new EventHandler(btn_Oper);

                  

                   bMul=new Button();

                   bMul.Size=new Size(25,25);

                   bMul.Location=new Point(130,80);

                   bMul.BackColor=Color.White;

                   bMul.Text="*";

                   bMul.Click+=new EventHandler(btn_Oper);

                  

                   bDiv=new Button();

                   bDiv.Size=new Size(25,25);

                   bDiv.Location=new Point(130,40);

                   bDiv.BackColor=Color.White;

                   bDiv.Text="/";

                   bDiv.Click+=new EventHandler(btn_Oper);

                  

                   bEqu=new Button();

                   bEqu.Size=new Size(25,25);

                   bEqu.Location=new Point(90,160);

                   bEqu.BackColor=Color.White;

                   bEqu.Text="=";

                   bEqu.Click+=new EventHandler(btn_equ);

                  

                   bClr=new Button();

                   bClr.Size=new Size(20,45);

                   bClr.Location=new Point(170,40);

                   bClr.BackColor=Color.Orange;

                   bClr.Text="AC";

                   bClr.Click+=new EventHandler(btn_clr);

                   p.Controls.Add(bDot);

                   p.Controls.Add(bPlus);

                   p.Controls.Add(bSub);

                   p.Controls.Add(bMul);

                   p.Controls.Add(bDiv);

                   p.Controls.Add(bEqu);

                   p.Controls.Add(bClr);

          }

         

          private void btn_clk(object obj,EventArgs ea) {

                   if(blnClear)

                             txtCalc.Text="";

                  

                   Button b3=(Button)obj;

                  

                   txtCalc.Text+=b3.Text;

                  

                   if (txtCalc.Text==".")

                             txtCalc.Text="0.";

                   dblSec=Convert.ToDouble(txtCalc.Text);

                  

                   blnClear=false;

          }

         

          private static void Main() {

                   Application.Run(new win());

          }

         

          private void btn_Oper(object obj,EventArgs ea) {

                   Button tmp=(Button)obj;

                   strOper=tmp.Text;

                   if (blnFrstOpen)

                             dblAcc=dblSec;

                   else

                             calc();

                   blnFrstOpen=false;

                   blnClear=true;

          }

          private void btn_clr(object obj,EventArgs ea) {

                   clear();

          }

          private void btn_equ(object obj,EventArgs ea) {

                   calc();

                  

          }

         

          private void calc() {

                   switch(strOper) {

                  

                             case "+":

                                      dblAcc+=dblSec;

                                      break;

                             case "-":

                                      dblAcc-=dblSec;

                                      break;

                             case "*":

                                      dblAcc*=dblSec;

                                      break;

                             case "/":

                                      dblAcc/=dblSec;

                                      break;

                   }

         

                   strOper="=";

                   blnFrstOpen=true;

                   txtCalc.Text=Convert.ToString(dblAcc);

                   dblSec=dblAcc;

          }

         

          private void clear() {

                   dblAcc=0;

                   dblSec=0;

                   blnFrstOpen=true;

                   txtCalc.Text="";

                   txtCalc.Focus();

          }

}