Monday, November 28, 2016

Download File From GridView Using ASP.Net



 <asp:FileUpload ID="FileUpload1" runat="server" />  
 <asp:Button ID="btnUpload" runat="server" Text="Upload" OnClick="UploadFile" />  
 <hr />  
 <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" EmptyDataText = "No files uploaded">  
   <Columns>  
     <asp:BoundField DataField="Text" HeaderText="File Name" />  
     <asp:TemplateField>  
       <ItemTemplate>  
         <asp:LinkButton ID="lnkDownload" Text = "Download" CommandArgument = '<%# Eval("Value") %>' runat="server" OnClick = "DownloadFile"></asp:LinkButton>  
       </ItemTemplate>  
     </asp:TemplateField>  
     <asp:TemplateField>  
       <ItemTemplate>  
         <asp:LinkButton ID = "lnkDelete" Text = "Delete" CommandArgument = '<%# Eval("Value") %>' runat = "server" OnClick = "DeleteFile" />  
       </ItemTemplate>  
     </asp:TemplateField>  
   </Columns>  
 </asp:GridView>  



Namespaces

You will need to import the following namespaces. C# using System.IO;


 Uploading the File and saving in directory or folder  
 When the file is selected in APS.Net FileUpload control and the Upload button is clicked the following event handler is triggered. Below I have folder Uploads in the root directory of my ASP.Net Website where I am saving the uploaded file.  
 C#  
 protected void UploadFile(object sender, EventArgs e)  
 {  
   string fileName = Path.GetFileName(FileUpload1.PostedFile.FileName);  
   FileUpload1.PostedFile.SaveAs(Server.MapPath("~/Uploads/") + fileName);  
   Response.Redirect(Request.Url.AbsoluteUri);  
 }  


 Displaying the files from folder or directory in ASP.Net GridView  
 Here I am reading all the files from the Uploads directory which I have created and then binding the fetched files to the ASP.Net GridView control.  
 C#  
 protected void Page_Load(object sender, EventArgs e)  
 {  
   if (!IsPostBack)  
   {  
     string[] filePaths = Directory.GetFiles(Server.MapPath("~/Uploads/"));  
     List<ListItem> files = new List<ListItem>();  
     foreach (string filePath in filePaths)  
     {  
       files.Add(new ListItem(Path.GetFileName(filePath), filePath));  
     }  
     GridView1.DataSource = files;  
     GridView1.DataBind();  
   }  
 }  


 Downloading the Uploaded File from ASP.Net GridView  
 The following event handler is executed when the lnkDownload LinkButton is clicked in the ASP.Net GridView Row. Using the CommandArgument property of the ASP.Net LinkButton, I get the path of the file using which I am downloading the file.  
 C#  
 protected void DownloadFile(object sender, EventArgs e)  
 {  
   string filePath = (sender as LinkButton).CommandArgument;  
   Response.ContentType = ContentType;  
   Response.AppendHeader("Content-Disposition", "attachment; filename=" + Path.GetFileName(filePath));  
   Response.WriteFile(filePath);  
   Response.End();  
 }  

Deleting the Uploaded File from ASP.Net GridView  
 The following event handler is executed when the lnkDelete LinkButton is clicked in the ASP.Net GridView Row. Using the CommandArgument property of the ASP.Net LinkButton, I get the path of the file using which I am deleting the file.  
 C#  
 
 protected void DeleteFile(object sender, EventArgs e)  
 {  
   string filePath = (sender as LinkButton).CommandArgument;  
   File.Delete(filePath);  
   Response.Redirect(Request.Url.AbsoluteUri);  
 }  

Wednesday, November 23, 2016

DropDownList Example in ASP.NET using C#

DropDownList Example in ASP.NET using C#

DropDownList.aspx (source code):

 <%@ Page Title="" Language="C#" MasterPageFile="~/RoseindiaMaster.master"  
 AutoEventWireup="true" CodeFile="DropDownList.aspx.cs" Inherits="DropDownList" %>  
 <asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">  
 <style type="text/css">  
 .style3  
 {  
 color: #800000;  
 }  
 </style>  
 </asp:Content>  
 <asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">  
 <div>  
 <h2 style="color:Green">DropDownList in ASP.NET 4 , C#</h2>  
 <strong><span class="style3">Enter first number:</span>  
 </strong>  
 <br />  
 <asp:TextBox ID="txt1" runat="server" Text="12"/>  
 <br />  
 <br />  
 <span class="style3">  
 <strong>Enter second number:  
 </strong>  
 </span>  
 <br />  
 <asp:TextBox ID="txt2" runat="server" Text="3" />  
 <br />  
 <br />  
 <span class="style3">  
 <strong>Select operation:  
 </strong>  
 </span>  
 <br />  
 <asp:DropDownList ID="drp1" runat="server" Width="145px"   
 Font-Bold="True" ForeColor="#006666"   
 onselectedindexchanged="drp1_SelectedIndexChanged" AutoPostBack="True">  
 <asp:ListItem>----Select----</asp:ListItem>  
 <asp:ListItem>Addition</asp:ListItem>  
 <asp:ListItem>Subtraction</asp:ListItem>  
 <asp:ListItem>Multiplication</asp:ListItem>  
 <asp:ListItem>Division</asp:ListItem>  
 </asp:DropDownList>  
 </div>  
 <br />  
 <asp:Label ID="label1" runat="server" Font-Bold="True" ForeColor="#000099" />  
 </asp:Content>  

DropDownList.aspx.cs (C# code file):

 using System;  
 using System.Collections.Generic;  
 using System.Linq;  
 using System.Web;  
 using System.Web.UI;  
 using System.Web.UI.WebControls;  
 public partial class DropDownList : System.Web.UI.Page  
 {  
 protected void Page_Load(object sender, EventArgs e)  
 {  
 }  
 protected void drp1_SelectedIndexChanged(object sender, EventArgs e)  
 {  
 double firstno = Convert.ToDouble(txt1.Text);  
 double secondno = Convert.ToDouble(txt2.Text);  
 if(drp1.SelectedIndex == 1)  
 {  
 double add = firstno + secondno;  
 label1.Text = "Addition is :" + add;  
 }  
 if (drp1.SelectedIndex == 2)  
 {  
 double sub = firstno - secondno;  
 label1.Text = "Subtraction is :" + sub;  
 }  
 if (drp1.SelectedIndex == 3)  
 {  
 double mul = firstno * secondno;  
 label1.Text = "Multiplication is :" + mul;  
 }  
 if (drp1.SelectedIndex == 4)  
 {  
 double div = firstno / secondno;  
 label1.Text = "Division is :" + div;  
 }  
 }  
 }  

OUTPUT


Tuesday, November 22, 2016

Dynamically change GridView Cell Background Color based on condition in ASP.Net using C#

The GridView Cell’s background color will be dynamically changed based on its value in the RowDataBound event of GridView.
GridView HTML Markup
The following HTML markup consists of an ASP.Net GridView consisting of two BoundField columns.


  <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" OnRowDataBound = "OnRowDataBound">
    <Columns>
        <asp:BoundField DataField="Item" HeaderText="Item" ItemStyle-Width = "100"/>
        <asp:BoundField DataField="Quantity" HeaderText="Quantity" ItemStyle-Width = "100"/>
    </Columns>
</asp:GridView>

Namespaces
You will need to import the following namespaces.
C#
using System.Data;
using System.Drawing;

Binding the ASP.Net GridView control
I have created a dynamic DataTable with some dummy data and it is used to populate the GridView control in the Page Load event.

 protected void Page_Load(object sender, EventArgs e)  
 {  
   if (!IsPostBack)  
   {  
     DataTable dt = new DataTable();  
     dt.Columns.AddRange(new DataColumn[2] { new DataColumn("Item"), new DataColumn("Quantity") });  
     dt.Rows.Add("Shirt", 145);  
     dt.Rows.Add("Jeans", 0);  
     dt.Rows.Add("Trousers", 190);  
     dt.Rows.Add("Tie", 30);  
     dt.Rows.Add("Cap", 0);  
     dt.Rows.Add("Hat", 90);  
     dt.Rows.Add("Scarf", 290);  
     dt.Rows.Add("Belt", 150);  
     GridView1.DataSource = dt;  
     GridView1.DataBind();  
   }  
 }  

Changing the Background color of GridView Row as per condition dynamically
Inside the OnRowDataBound event handler of the GridView, the Cell value is compared with different quantity ranges and based on the following quantity range values, the background color of the GridView Cell will change.
 protected void OnRowDataBound(object sender, GridViewRowEventArgs e)  
 {  
   if (e.Row.RowType == DataControlRowType.DataRow)  
   {  
     TableCell cell = e.Row.Cells[1];  
     int quantity = int.Parse(cell.Text);  
     if (quantity == 0)  
     {  
       cell.BackColor = Color.Red;  
     }  
     if (quantity > 0 && quantity <= 50)  
     {  
       cell.BackColor = Color.Yellow;  
     }  
     if (quantity > 50 && quantity <= 100)  
     {  
       cell.BackColor = Color.Orange;  
     }  
   }  
 }  


Insert, Update, Delete In GridView Using ASP.Net C#

Using Gridview & SIngle store Procedure Insert, Update, Delete In GridView with sql server



I have set the primary key on the id column and I have set the Identity specification to Yes.
Now we have a table to perform these operations for. Now let us start to create the Stored Procedure.
The Stored Procedure is created using the keyword "Create Procedure" followed by the procedure name. Let us create the Stored Prcedure named "EmpEntry" as in the following:

 create Procedure EmpEntry  
 (  
  --variable declareations   
  @Action Varchar (10),  --to perform operation according to string ed to this varible such as Insert,update,delete,select     
  @id int=null,  --id to perform specific task  
  @FnameVarchar (50)=null,  -- for FirstName  
  @MName Varchar (50)=null,  -- for MName  
  @Lname Varchar (50)=null  -- for LastName  
 )  
 as  
 Begin   
  SET NOCOUNT ON;  
 If @Action='Insert'  --used to insert records  
 Begin  
   Insert Into employee (FirstName,MName,LastName)values(@Fname,@MName,@Lname)  
 End   
 else if @Action='Select'  --used to Select records  
 Begin  
   select *from employee  
 end  
 else if @Action='Update' --used to update records  
 Begin  
   update employeeset FirstName=@Fname,MName=@MName,LastName=@Lname where id=@id  
  End  
  Else If @Action='delete' --used to delete records  
  Begin  
   delete from employeewhere id=@id  
  end  
  End  

The comments in the Stored Procedure above clearly explain which block is used for which purpose, so I have briefly explained it again. I have used the @Action variable and assigned the string to them and according to the parameter ed to the Stored Procedure the specific block will be executed because I have kept these blocks or conditions in nested if else if conditional statements.
"The most important thing is that I have assigned null to each variable to avoid the effect on the parameter ed to the Stored Procedure because we are ing a different number of parameters but not the same number of parameters to the Stored Procedure to perform these tasks."
Now create the one sample application "Empsys" as:
  1. "Start" - "All Programs" - "Microsoft Visual Studio 2010".
  2. "File" - "New Project" - "C#" - "Empty Web Application" (to avoid adding a master page).
  3. Provide the web site a name such as  "Empsys" or another as you wish and specify the location.
  4. Then right-click on Solution Explorer - "Add New Item" - "Default.aspx page".
  5. Drag and drop one button, three textboxes, one GridView and one hidden field to the hidden value to the database and one label on the 
     section of the Default.aspx page.
Then switch to the design view;
 <form id="form1"runat="server">  
   <div>  
 First Name <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>  
 Middle Name<asp:TextBox ID="TextBox2" runat="server"></asp:TextBox>  
 Last Name <asp:TextBox ID="TextBox3" runat="server"></asp:TextBox>  
     <asp:ButtonID="Button1"runat="server"Text="save"onclick="Button1_Click" />  
   </div>  
 <asp:HiddenField ID="HiddenField1" runat="server"/>  
  <asp:GridViewID="GridView1"runat="server" >  
    </asp:GridView>  
 </form>  

Now use the following GridView event properties to perform events such as update, delete, edit cancel and so on. Let us see what the properties are:
  • DataKeyNames: This property I have used to the the row index of GridView  
  • OnRowEditing: This property is used to handle the event when the user clicks on the edit button
  • OnRowCancelingEdit: This property is used to handle the event when the user clicks on the Cancel button that exists after clicking on the edit button
  • OnRowDeleting: This property is used to handle the event when the user clicks on the delete button that deletes the row of the GridView
  • OnRowUpdating: This property is used to handle the event when the user clicks on the update button that updates the Grid Record 
Now my grid will look such as the following:
   
  

On the preceding GridView properties I have assigned the method name to be called for particular operations.

 Method to Insert Data in Database   
 Right-click from the design page and view the code and then write the following code in the default.aspx.cs page to save the inserted records in the database:  
 protected void empsave(object sender, EventArgs e)  
 {  
    connection();  
    query = "studentEntryView";     //Stored Procedure name   
    SqlCommand com = new SqlCommand(query, con); //creating SqlCommand object  
    com.CommandType = CommandType.StoredProcedure; //here we declaring command type as stored Procedure  
     /* adding paramerters to SqlCommand below *\  
    com.Parameters.AddWithValue("@Action", HiddenField1.Value).ToString();//for ing hidden value to preform insert operation  
     com.Parameters.AddWithValue("@FName",TextBox1.Text.ToString());    //first Name  
     com.Parameters.AddWithValue("@Mname ", TextBox2.Text.ToString());   //middle Name  
     com.Parameters.AddWithValue("@LName ",TextBox3.Text.ToString());    //Last Name  
     com.ExecuteNonQuery();           //executing the sqlcommand  
     Label1.Visible = true;  
     Label1.Text = "Records are Submitted Successfully";  
 }  
 Now create the mehtod to view the records in the GridView:  
 public void viewdata()  
 {  
   connection();  
   query = "studentEntryView";  
   SqlCommand com = new SqlCommand(query, con);  
   com.CommandType = CommandType.StoredProcedure;  
   com.Parameters.AddWithValue("@Action", HiddenField2.Value).ToString();  
   DataSet ds =new DataSet();  
   SqlDataAdapter da = new SqlDataAdapter(com);  
   da.Fill(ds);  
   GridView1.DataSource = ds;  
   GridView1.DataBind();  
 }  
 The following is method for the "OnRowEditing" Event:  
 protected void edit(objectsender, GridViewEditEventArgs e)  
 {  
   GridView1.EditIndex= e.NewEditIndex;  
   gedata();  
 }  
 The following is method for the "OnRowCancelingEdit" Event:  
 protected void canceledit(object sender, GridViewCancelEditEventArgs e)  
 {  
   GridView1.EditIndex = -1;  
   gedata();  
 }  
 The following is method for the "OnRowDeleting" Event:  
 protected void delete(object sender, GridViewDeleteEventArgs e)  
 {  
    connection();  
    int id = int.Parse(GridView1.DataKeys[e.RowIndex].Value.ToString());  
    HiddenField1.Value = "Delete";  
    query = "EmpEntry";  
    com = new SqlCommand(query, con);  
    com.CommandType =CommandType .StoredProcedure;  
    com.Parameters.AddWithValue("@Action", HiddenField1.Value).ToString();  
    com.Parameters.AddWithValue("id", SqlDbType.Int).Value = id;  
    com.ExecuteNonQuery();  
    con.Close();  
    gedata();           
  }  
 The following is method for the "OnRowUpdating" Event:  
 protected void update(object sender, GridViewUpdateEventArgs e)  
 {  
    connection();  
    int id=int.Parse(GridView1.DataKeys[e.RowIndex].Value.ToString());  
    HiddenField1.Value = "update";  
    query = "EmpEntry";  
    com = new SqlCommand(query, con);  
    com.CommandType = CommandType.StoredProcedure;  
    com.Parameters.AddWithValue("@Action", HiddenField1.Value).ToString();  
    com.Parameters.AddWithValue("@FName", ((TextBox)GridView1.Rows[e.RowIndex].Cells[3].Controls[0]).Text.ToString());  
    com.Parameters.AddWithValue("@MName", ((TextBox)GridView1.Rows[e.RowIndex].Cells[4].Controls[0]).Text.ToString());  
    com.Parameters.AddWithValue("@LName", ((TextBox)GridView1.Rows[e.RowIndex].Cells[5].Controls[0]).Text.ToString());  
    com.Parameters.AddWithValue("@id", SqlDbType.int ).Value = id;  
    com.ExecuteNonQuery();  
    con.Close();  
    GridView1.EditIndex = -1;  
    gedata();  
 }  

Brief introduction to the codeIn the sample code above I have used the two string queries for giving the Stored Procedure name and the constr for storing the connection from the web.config file and another thing is that I have used a hidden field by which I am ing the action values that are required to our Stored Procedure.

Now our application is ready to use, press F5 or other as you know, then enter the some values to TextBox and press the "Save" button.


Now after clicking on the "Save" button, the hidden field value takes the value "Insert" and es it to the Stored Procedure as the action and because of this the Stored Procedure will execute a particular type of block.

Now at page load I have called the method, so after that the grid will fill as in:




Now click on the Edit button that calls the edit method as shown in the following grid:



If you click on the "Cancel" button then the editcancel method will be called and edit mode will be cancelled. Now enter some values into the grid TextBox and click on an update button that calls the update method and then the records in the GridView will be updated as in:




Monday, November 21, 2016

RadioButton value save into Database in ASP.Net using C#

 RadioButton value save into  Database in ASP.Net using C# 


 <table border="0" cellpadding="0" cellspacing="0">  
   <tr>  
     <td>  
       Name:  
     </td>  
     <td>  
       <asp:TextBox ID="txtName" runat="server" />  
     </td>  
   </tr>  
   <tr>  
     <td>  
       Gender:  
     </td>  
     <td>  
       <asp:RadioButton ID="rbMale" Text="Male" runat="server" GroupName="Gender" />  
       <asp:RadioButton ID="rbFemale" Text="Female" runat="server" GroupName="Gender" />  
     </td>  
   </tr>  
   <tr>  
     <td>  
     </td>  
     <td>  
       <asp:Button Text="Submit" runat="server" OnClick="Submit" />  
     </td>  
   </tr>  
 </table>  


 protected void Submit(object sender, EventArgs e)  
 {  
   string name = txtName.Text.Trim();  
   string gender = string.Empty;  
   if (rbMale.Checked)  
   {  
     gender = "M";  
   }  
   else if (rbFemale.Checked)  
   {  
     gender = "F";  
   }  
   string constr = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;  
   using (SqlConnection con = new SqlConnection(constr))  
   {  
     using (SqlCommand cmd = new SqlCommand("INSERT INTO Persons(Name, Gender) VALUES(@Name, @Gender)"))  
     {  
       cmd.Connection = con;  
       cmd.Parameters.AddWithValue("@Name", name);  
       cmd.Parameters.AddWithValue("@Gender", gender);  
       con.Open();  
       cmd.ExecuteNonQuery();  
       con.Close();  
     }  
   }  
 }  

CheckBox Control in c#

CheckBoxes allow the user to make multiple selections from a number of options. CheckBox to give the user an option, such as true/false or yes/no. You can click a check box to select it and click it again to deselect it.



 using System;  
 using System.Drawing;  
 using System.Windows.Forms;  
 namespace WindowsFormsApplication1  
 {  
   public partial class Form1 : Form  
   {  
     public Form1()  
     {  
       InitializeComponent();  
     }  
     private void button1_Click(object sender, EventArgs e)  
     {  
       string msg = "";  
       if (checkBox1.Checked == true)  
       {  
         msg = "net-informations.com";  
       }  
       if (checkBox2.Checked == true)  
       {  
         msg = msg + "  vb.net-informations.com";  
       }  
       if (checkBox3.Checked == true)  
       {  
         msg = msg + "  csharp.net-informations.com";  
       }  
       if (msg.Length > 0)  
       {  
         MessageBox.Show (msg + " selected ");  
       }  
       else  
       {  
         MessageBox.Show ("No checkbox selected");  
       }  
       checkBox1.ThreeState = true;  
     }  
   }  
 }  

Saturday, November 19, 2016

Calculator using ASP.net

Basic Calculator in C#

Process to create calculator

First we need to create a TextBox and 16 Buttons as in the following:
  • 10 Buttons for numbers (0-9)
  • 5 Buttons to perform operation (addition (+), Subtraction (-) , Multiplication (*), Division (/) ,Clear (CLR) )
  • 1 Buttons for evaluation (=)
Here is the code for the "Default.aspx" page:


 <html xmlns="http://www.w3.org/1999/xhtml">  
 <head id="Head1" runat="server">  
   <title></title>  
   <style type="text/css">  
   .cal  
   {  
     position:absolute;  
     top:50px;  
     left:150px;  
     right:400px;  
     height:500px;  
     bottom:100px;  
     background-color:Teal;  
     }  
   </style>  
 </head>  
 <body>  
   <form id="form1" runat="server">  
   <div class="cal">  
     <asp:Label ID="l" Text=" BASIC CALCULATOR" runat="server" Style="margin-left: 200px"  
       Font-Bold="False" Font-Italic="False"></asp:Label>  
     <asp:TextBox ID="t" runat="server" Style="margin-left: 100px; margin-top: 24px;"  
       Width="335px" Height="41px"></asp:TextBox>  
     <asp:Button ID="b1" Text="1" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b1_Click" />  
     <asp:Button ID="b2" Text="2" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b2_Click" />  
     <asp:Button ID="b3" Text="3" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b3_Click" />  
     <asp:Button ID="add" Text="+" runat="server" Height="37px" Style="margin-left: 0px;  
       margin-top: 0px;" Width="57px" OnClick="add_Click" />  
     <asp:Button ID="b4" Text="4" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b4_Click" />  
     <asp:Button ID="b5" Text="5" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b5_Click" />  
     <asp:Button ID="b6" Text="6" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b6_Click" />  
     <asp:Button ID="sub" Text="-" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="sub_Click" />  
     <asp:Button ID="b7" Text="7" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b7_Click" />  
     <asp:Button ID="b8" Text="8" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b8_Click" />  
     <asp:Button ID="b9" Text="9" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b9_Click" />  
     <asp:Button ID="mul" Text="*" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="mul_Click" />  
     <asp:Button ID="b0" runat="server" Text="0" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="b0_Click" />  
     <asp:Button ID="clr" runat="server" Text="CLR" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="clr_Click" />  
     <asp:Button ID="eql" runat="server" Text="=" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="eql_Click" />  
     <asp:Button ID="div" Text="/" runat="server" Height="37px" Style="margin-left: 0px"  
       Width="57px" OnClick="div_Click" />  
   </div>  
   </form>  
 </body>  
 </html>  

Here is the code for the "Default.aspx.cs" page (the code for all the buttons) :

 Here is the code for the "Default.aspx.cs" page (the code for all the buttons) :  
 using System;  
 using System.Collections.Generic;  
 using System.Linq;  
 using System.Web;  
 using System.Web.UI;  
 using System.Web.UI.WebControls;  
 public partial class _Default : System.Web.UI.Page  
 {  
   static float a, c, d;  
   static char b;  
   protected void Page_Load(object sender, EventArgs e)  
   {  
   }  
   protected void b1_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b1.Text;  
     }  
     else  
       t.Text = t.Text + b1.Text;  
   }  
   protected void b2_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b2.Text;  
     }  
     else  
       t.Text = t.Text + b2.Text;  
   }  
   protected void b3_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b3.Text;  
     }  
     else  
       t.Text = t.Text + b3.Text;  
   }  
   protected void b4_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b4.Text;  
     }  
     else  
       t.Text = t.Text + b4.Text;  
   }  
   protected void b5_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b5.Text;  
     }  
     else  
       t.Text = t.Text + b5.Text;  
   }  
   protected void b6_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b6.Text;  
     }  
     else  
       t.Text = t.Text + b5.Text;  
   }  
   protected void b7_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b7.Text;  
     }  
     else  
       t.Text = t.Text + b7.Text;  
   }  
   protected void b8_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b8.Text;  
     }  
     else  
       t.Text = t.Text + b8.Text;  
   }  
   protected void b9_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b9.Text;  
     }  
     else  
       t.Text = t.Text + b9.Text;  
   }  
   protected void b0_Click(object sender, EventArgs e)  
   {  
     if ((t.Text == "+") || (t.Text == "-") || (t.Text == "*") || (t.Text == "/"))  
     {  
       t.Text = "";  
       t.Text = t.Text + b0.Text;  
     }  
     else  
       t.Text = t.Text + b0.Text;  
   }  
   protected void add_Click(object sender, EventArgs e)  
   {  
     a = Convert.ToInt32(t.Text);  
     t.Text = "";  
     b = '+';  
     t.Text += b;  
   }  
   protected void sub_Click(object sender, EventArgs e)  
   {  
     a = Convert.ToInt32(t.Text);  
     t.Text = "";  
     b = '-';  
     t.Text += b;  
   }  
   protected void mul_Click(object sender, EventArgs e)  
   {  
     a = Convert.ToInt32(t.Text);  
     t.Text = "";  
     b = '*';  
     t.Text += b;  
   }  
   protected void div_Click(object sender, EventArgs e)  
   {  
     a = Convert.ToInt32(t.Text);  
     t.Text = "";  
     b = '/';  
     t.Text += b;  
   }  
   protected void eql_Click(object sender, EventArgs e)  
   {  
     c = Convert.ToInt32(t.Text);  
     t.Text = "";  
     if (b == '/')  
     {  
       d = a / c;  
       t.Text += d;  
       a = d;  
     }  
     else if (b == '+')  
     {  
       d = a + c;  
       t.Text += d;  
       a = d;  
     }  
     else if (b == '-')  
     {  
       d = a - c;  
       t.Text += d;  
       a = d;  
     }  
     else  
     {  
       d = a * c;  
       t.Text += d;  
       a = d;  
     }  
   }  
   protected void clr_Click(object sender, EventArgs e)  
   {  
     t.Text = "";  
   }  
 }