Calculator Program/Application using Asp.Net

Creating calculator application is very simple using Asp.Net.
 

Web form: 

<table>
        <tr>
            <td colspan="4">
                 </td>
        </tr>
        <tr>
            <td colspan="4">
                <asp:TextBox ID="DisplayTextBox1" runat="server" Height="45px" Width="375px"
                    TextMode="MultiLine" Font-Bold="True" Font-Size="X-Large" ReadOnly="True"></asp:TextBox>
            </td>
        </tr>
        <tr>
            <td colspan="4" height="30px">
                <asp:Label ID="Answer" runat="server" Font-Bold="True"
                    Font-Size="X-Large"></asp:Label>
            </td>
        </tr>
        <tr>
            <td>
                <asp:Button ID="Button21" runat="server" Height="50px" Text="("
                    Width="95px" onclick="Button21_Click" />
            </td>
            <td>
                <asp:Button ID="Button22" runat="server" Height="50px" Text=")"
                    Width="95px" onclick="Button22_Click" />
            </td>
            <td>
                <asp:Button ID="Button24" runat="server" Height="50px" Text="DEL"
                    Width="95px" onclick="Button24_Click" />
            </td>
            <td>
                <asp:Button ID="Button25" runat="server" Height="50px" Text="AC"
                    Width="95px" onclick="Button25_Click" />
            </td>
        </tr>
        <tr>
            <td>
                <asp:Button ID="ButtonNumber7" runat="server" Height="50px" Text="7"
                    Width="95px" onclick="ButtonNumber7_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumber8" runat="server" Height="50px" Text="8"
                    Width="95px" onclick="ButtonNumber8_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumber9" runat="server" Height="50px" Text="9"
                    Width="95px" onclick="ButtonNumber9_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumberDevide" runat="server" Height="50px" Text="÷"
                    Width="95px"  ForeColor="Black"
                    onclick="ButtonNumberDevide_Click" />
            </td>
        </tr>
        <tr>
            <td>
                <asp:Button ID="ButtonNumber4" runat="server" Height="50px" Text="4"
                    Width="95px" onclick="ButtonNumber4_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumber5" runat="server" Height="50px" Text="5"
                    Width="95px" onclick="ButtonNumber5_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumber6" runat="server" Height="50px" Text="6"
                    Width="95px" onclick="ButtonNumber6_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumberMulti" runat="server" Height="50px" Text="X"
                    Width="95px"  onclick="ButtonNumberMulti_Click" />
            </td>
        </tr>
        <tr>
            <td>
                <asp:Button ID="ButtonNumber1" runat="server" Height="50px" Text="1"
                    Width="95px" onclick="ButtonNumber1_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumber2" runat="server" Height="50px" Text="2"
                    Width="95px" onclick="ButtonNumber2_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumber3" runat="server" Height="50px" Text="3"
                    Width="95px" ClientIDMode="AutoID" onclick="ButtonNumber3_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumberMinus" runat="server" Height="50px" Text="_"
                    Width="95px"  onclick="ButtonNumberMinus_Click" />
            </td>
        </tr>
        <tr>
            <td>
                <asp:Button ID="ButtonNumber0" runat="server" Height="50px" Text="0"
                    Width="95px" onclick="ButtonNumber0_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumberdot" runat="server" Height="50px" Text="."
                    Width="95px" onclick="ButtonNumberdot_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumberEqual" runat="server" Height="50px" Text="="
                    Width="95px"  onclick="ButtonNumberEqual_Click" />
            </td>
            <td>
                <asp:Button ID="ButtonNumberPlus" runat="server" Height="50px" Text="+"
                    Width="95px"  onclick="ButtonNumberPlus_Click" />
            </td>
        </tr>
    </table>

C#:

 

Add the following namespace. 

using System.Data;

Add the following code inside the .cs page.

protected void Button21_Click(object sender, EventArgs e)
{
    DisplayTextBox1.Text = DisplayTextBox1.Text + "(";
}

protected void Button22_Click(object sender, EventArgs e)
{
    DisplayTextBox1.Text = DisplayTextBox1.Text + ")";
}


protected void Button25_Click(object sender, EventArgs e)
{
    DisplayTextBox1.Text = "";
    Answer.Text = "";
}

protected void Button24_Click(object sender, EventArgs e)
{
    string DisplayText = DisplayTextBox1.Text;
    int LastIndex = DisplayText.Length;
    DisplayTextBox1.Text = DisplayTextBox1.Text.Remove(LastIndex - 1);

}

protected void ButtonNumberEqual_Click(object sender, EventArgs e)
{

    try
    {
        string Input = DisplayTextBox1.Text;
        DataTable table = new DataTable();
        Object answer;
        answer = table.Compute(Input, null);
        Answer.Text = answer.ToString();
    }

    catch
    {
        Answer.Text = "ERROR :(";
    }

}

Now run the program :) 

 

 jhg