How To Create A Calculator In C#
In This C# Tutorial we will See How To Make A Simple Windows Form Calculator Application With Swith To Do The Basic Operations (+, -, /, *) And Reset To Make Another Calc Using C# In Visual Studio Editor .
Part 1
Part 2
Part 3
Part 4
Project Source Code:
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace WindowsFormsApplication1
{
public partial class csharp_calculator : Form
{
public csharp_calculator()
{
InitializeComponent();
}
float num1 = 0, num2 = 0;
int oprClickCount = 0;
bool isOprClick = false, isEqualClick = false;
string opr;
private void csharp_calculator_Load(object sender, EventArgs e)
{
// add button click event to all buttons
foreach(Control c in Controls)
{
if(c is Button)
{
if(c.Text != "Reset")
c.Click += new System.EventHandler(btn_click);
}
}
}
// create button click event
public void btn_click(object sender, EventArgs e)
{
Button button = (Button)sender;
if (!isOperator(button))// if the button is a number
{
if(isOprClick)
{
num1 = float.Parse(textBox1.Text);
textBox1.Text = "";
}
// if the textbox text not contain "."
if (!textBox1.Text.Contains("."))
{
if (textBox1.Text.Equals("0") && !button.Text.Equals("."))
{
// delete the first "0"
// set button text to the textbox
// if the button text is not "."
textBox1.Text = button.Text;
isOprClick = false;
}
else
{
textBox1.Text += button.Text;
isOprClick = false;
}
}
else if (!button.Text.Equals("."))
{
textBox1.Text += button.Text;
isOprClick = false;
}
}
else // if the button is an operator [+ - / * =]
{
if(oprClickCount == 0)// if it's the first time we click on an operator
{
oprClickCount++;
// convert textbox text to float and set it into num1
num1 = float.Parse(textBox1.Text);
// get the operator from button text
opr = button.Text;
// set oprclick to true
isOprClick = true;
}
else
{
if(!button.Text.Equals("="))// if the operation is not "="
{
if(!isEqualClick)
{
num2 = float.Parse(textBox1.Text);
textBox1.Text = Convert.ToString(calc(opr, num1, num2));
num2 = float.Parse(textBox1.Text);
opr = button.Text;
isOprClick = true;
isEqualClick = false;
}else
{
isEqualClick = false;
opr = button.Text;
}
}
else
{
num2 = float.Parse(textBox1.Text);
textBox1.Text = Convert.ToString(calc(opr, num1, num2));
num1 = float.Parse(textBox1.Text);
isOprClick = true;
isEqualClick = true;
}
}
}
}
// create a function to check if the clicked button is a number(+ '.') or an operators
public bool isOperator(Button button)
{
string buttonText = button.Text;
if(buttonText.Equals("+") || buttonText.Equals("-") ||
buttonText.Equals("X") || buttonText.Equals("/") ||
buttonText.Equals("="))
{
return true;
}
else
{
return false;
}
}
// function to calculate
public float calc(string opr, float n1, float n2)
{
float result = 0;
switch (opr)
{
case"+":
result = n1 + n2;
break;
case "-":
result = n1 - n2;
break;
case "X":
result = n1 * n2;
break;
case "/":
if(n2 != 0)
result = n1 / n2;
break;
}
return result;
}
// button reset to make another calculation
private void buttonReset_Click(object sender, EventArgs e)
{
num1 = 0;
num2 = 0;
opr = "";
isOprClick = false;
isEqualClick = false;
oprClickCount = 0;
textBox1.Text = "0";
}
}
}
OUTPUT:
More C# Projects:
Download Projects Source Code