calculadora simplona

using System.IO;
 
namespace Calculadora
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
 
double a;
double b;
string c;
 
private void btn1_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "1";
}
else
{
txtpantalla.Text = txtpantalla.Text + "1" ;
}
}
 
private void btn2_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "2";
}
else
{
txtpantalla.Text = txtpantalla.Text + "2";
}
}
 
private void btn3_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "3";
}
else
{
txtpantalla.Text = txtpantalla.Text + "3";
}
}
 
private void btn4_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "4";
}
else
{
 txtpantalla.Text = txtpantalla.Text + "4";
}
}
 
private void btn5_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "5";
}
else
{
txtpantalla.Text = txtpantalla.Text + "5";
}
}
 
private void btn6_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "6";
}
else
{
txtpantalla.Text = txtpantalla.Text + "6";
}
}
 
private void btn7_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "7";
}
else
{
txtpantalla.Text = txtpantalla.Text + "7";
}
}
 
private void btn8_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "8";
}
else
{
txtpantalla.Text = txtpantalla.Text + "8";
}
}
 
private void btn9_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "9";
}
else
{
txtpantalla.Text = txtpantalla.Text + "9";
 }
}
 
private void btn0_Click(object sender, EventArgs e)
{
if (txtpantalla.Text == "")
{
txtpantalla.Text = "0";
}
else
{
txtpantalla.Text = txtpantalla.Text + "0";
}
}
 
private void btndivision_Click(object sender, EventArgs e)
{
a = Convert.ToDouble(this.txtpantalla.Text);
c = "/";
this.txtpantalla.Clear();
this.txtpantalla.Focus();
}
 
private void btnmultiplicacion_Click(object sender, EventArgs
e)
{
a = Convert.ToDouble(this.txtpantalla.Text);
c = "*";
this.txtpantalla.Clear();
this.txtpantalla.Focus();
}
 
private void btnresta_Click(object sender, EventArgs e)
{
a = Convert.ToDouble(this.txtpantalla.Text);
c = "-";
this.txtpantalla.Clear();
this.txtpantalla.Focus();
}
 
private void btnsuma_Click(object sender, EventArgs e)
{
a = Convert.ToDouble(this.txtpantalla.Text);
c = "+";
this.txtpantalla.Clear();
this.txtpantalla.Focus();
}
 
private void btnpunto_Click(object sender, EventArgs e)
{
if (this.txtpantalla.Text.Contains('.')==false)
{
this.txtpantalla.Text = this.txtpantalla.Text + ".";
}
 
 
}
 
private void btnigual_Click(object sender, EventArgs e)
{
b = Convert.ToDouble(this.txtpantalla.Text);
 switch (c)
{
case "+":
this.txtpantalla.Text = Convert.ToString (b + a);
break;
 
case "-":
this.txtpantalla.Text = Convert.ToString(b - a);
break;
 
case "*":
this.txtpantalla.Text = Convert.ToString(b * a);
break;
 
case "/":
this.txtpantalla.Text = Convert.ToString(b / a);
break;
}
 
 
}
 
private void btnprint_Click(object sender, EventArgs e)
{
StreamWriter Archivo = new StreamWriter("Ruta\\
archivo.txt");
Archivo.WriteLine("Operaciones: " + a + c + b + "=" +
this.txtpantalla.Text);
Archivo.Flush();
Archivo.Close();
 
System.Diagnostics.Process.Start("Ruta\\archivo.txt");
}
 
private void btnlimpiar_Click(object sender, EventArgs e)
{
a = Convert.ToDouble("");
b = Convert.ToDouble("");
this.txtpantalla.Text = "";
 
}
}
}

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