Building a Calculator using C#

Question

I would like to build a basic calculator using C#.

However, I aim to build one which performs calculation only after the equal button is clicked.

For example, when someone type in "10+12/2-2", the calculator will display "10+12/2-2 = 10" after the "=" button is clicked.

Any idea how to do it?

Thank you very much for your help.

Dipankar Biswas · Answer

Code: using System; using System.Collections.Generic; using System.ComponentModel; using System.Data; using System.Drawing; using System.Text; using System.Windows.Forms; namespace work1 { public partial class Form1 : Form { public Form1() { InitializeComponent(); } private double num1; private double num2; private string cal; private bool inputstatus = true; private void button1_Click(object sender, EventArgs e) { if (inputstatus) { if (textBox1.Text.Length >= 1) { textBox1.Text += button1.Text; } } } private void button2_Click(object sender, EventArgs e) { if (inputstatus) { textBox1.Text += button2.Text; } else { textBox1.Text = button2.Text; inputstatus = true; } } private void button3_Click(object sender, EventArgs e) { if (inputstatus) { textBox1.Text += button3.Text; } else { textBox1.Text = button3.Text; inputstatus = true; } } private void button4_Click(object sender, EventArgs e) { if (inputstatus) { textBox1.Text += button4.Text; } else { textBox1.Text = button4.Text; inputstatus = true; } } private void button5_Click(object sender, EventArgs e) { if (inputstatus) { textBox1.Text += button5.Text; } else { textBox1.Text = button5.Text; inputstatus = true; } } private void button6_Click(object sender, EventArgs e) { if (inputstatus) { textBox1.Text += button6.Text; } else { textBox1.Text = button6.Text; inputstatus = true; } } private void button7_Click(object sender, EventArgs e) { if (inputstatus) { textBox1.Text += button7.Text; } else { textBox1.Text = button7.Text; inputstatus = true; } } private void button8_Click(object sender, EventArgs e) { if (inputstatus) { textBox1.Text += button8.Text; } else { textBox1.Text = button8.Text; inputstatus = true; } } private void button9_Click(object sender, EventArgs e) { if (inputstatus) { textBox1.Text += button9.Text; } else { textBox1.Text = button9.Text; inputstatus = true; } } private void button10_Click(object sender, EventArgs e) { if (inputstatus) { textBox1.Text += button10.Text; } else { textBox1.Text = button10.Text; inputstatus = true; } } private void button11_Click(object sender, EventArgs e) { if (textBox1.Text.Length != 0) { num1 = System.Double.Parse(textBox1.Text); result(); cal = "+"; } } private void button12_Click(object sender, EventArgs e) { if (textBox1.Text.Length != 0) { num1 = System.Double.Parse(textBox1.Text); result(); cal = "-"; } } private void button13_Click(object sender, EventArgs e) { if (textBox1.Text.Length != 0) { num1 = System.Double.Parse(textBox1.Text); result(); cal = "*"; } } private void button14_Click(object sender, EventArgs e) { if (textBox1.Text.Length != 0) { num1 = System.Double.Parse(textBox1.Text); result(); cal = "/"; } } private void button16_Click(object sender, EventArgs e) { result(); cal = string.Empty; } private void button15_Click(object sender, EventArgs e) { textBox1.Text = string.Empty; num2 = 0; cal = string.Empty; } private void result() { num2 = System.Double.Parse(textBox1.Text); switch (cal) { case "+": num1 = num1 + num2; break; case "-": num1 = num1 - num2; break; case "*": num1 = num1 * num2; break; case "/": num1 = num1 / num2; break; } textBox1.Text = num1.ToString(); inputstatus = false; } private void copyToolStripMenuItem_Click(object sender, EventArgs e) { textBox1.Copy(); } private void pasteCtrlVToolStripMenuItem_Click(object sender, EventArgs e) { textBox1.Paste(); } private void cutCtrlXToolStripMenuItem_Click(object sender, EventArgs e) { textBox1.Cut(); } } }

Sagar Pardeshi · Answer

Hi aane, follow below url it's help u...... http://code.msdn.microsoft.com/windowsdesktop/Simple-Calculator-d1d8cf4c

Abhishek Yadav · Answer

Hello Anne Leong, Please find the below link to get solution of your question. http://www.codeproject.com/Articles/88435/Simple-Guide-to-Mathematical-Expression-Parsing Hope this will help you..

Mahesh Chand · Answer

Search this website. There are many code samples.