Update,Delete and Insert Data into FormView

now, i will explain how to data bind in formview and update,delete,cancle event .
here,aspx page

<asp:FormView ID="fv" runat="server" AllowPaging="True" OnPageIndexChanging="fv_PageIndexChanging">

        <HeaderTemplate>

            <table>

                <tr>

                    <td width="100px">

                        Id:

                    </td>

                    <td width="100px">

                        Name:

                    </td>

                    <td width="100px">

                        Marks:

                    </td>

                </tr>

            </table>

        </HeaderTemplate>

        <ItemTemplate>

            <table>

                <tr>

                    <td width="100px">

                        <asp:Label ID="lblid" runat="server" Text='<%#Eval("sid") %>'></asp:Label>

                    </td>

                    <td width="100px">

                        <asp:Label ID="lblname" runat="server" Text='<%#Eval("sname") %>'></asp:Label>

                    </td>

                    <td width="100px">

                        <asp:Label ID="lblmarks" runat="server" Text='<%#Eval("marks") %>'></asp:Label>

                    </td>

                </tr>

            </table>           

            <asp:LinkButton ID="btnedit" runat="server" OnClick="btnedit_Click">Edit</asp:LinkButton>

            <asp:LinkButton ID="btninsert" runat="server" onclick="btninsert_Click">Insert</asp:LinkButton>

            <asp:LinkButton ID="btndelete" runat="server" onclick="btndelete_Click">Delete</asp:LinkButton>

        </ItemTemplate>

        <EditItemTemplate>

            <table>

                <tr>

                    <td width="100px">

                        <asp:Label ID="lblid" runat="server" Text='<%#Eval("sid")%>'></asp:Label>

                    </td>

                    <td width="100px">

                        <asp:TextBox ID="txtname" runat="server" Text='<%#Bind("sname") %>'></asp:TextBox>

                    </td>

                    <td width="100px">

                        <asp:TextBox ID="txtmarks" runat="server" Text='<%#Bind("marks") %>'></asp:TextBox>

                    </td>

                </tr>

            </table>           

            <br>           

            </br>

            <asp:LinkButton ID="btnupdate" runat="server" OnClick="btnupdate_Click">Update</asp:LinkButton>

            <asp:LinkButton ID="btncancle" runat="server" OnClick="btncancle_Click">Cancle</asp:LinkButton>     

                  

        </EditItemTemplate>

    </asp:FormView>

After that write the following code aspx.cs page

using System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using System.Data;

using System.Data.SqlClient;

public partial class _Default : System.Web.UI.Page

{

     static SqlConnection con = new SqlConnection("Data Source -PC\\SQLEXPRESS;Initial Catalog;Integrated Security=True;Pooling=False");

     static SqlDataAdapter da = new SqlDataAdapter("select *from student",con);

     SqlCommandBuilder cmdb = new SqlCommandBuilder(da);

     DataTable dt = new DataTable();

      

    protected void Page_Load(object sender, EventArgs e)

    {

        if (Page.IsPostBack == false)

        {

            da.Fill(dt);

            ViewState["dt"] = dt;

            bind();

        }

        else

        {

            dt = (DataTable)ViewState["dt"];

        }

    }

    protected void bind()

    {

        fv.DataSource = dt;

        fv.DataBind();

    }

    protected void fv_PageIndexChanging(object sender, FormViewPageEventArgs e)

    {

        fv.PageIndex = e.NewPageIndex;

        bind();

    }

    protected void btnedit_Click(object sender, EventArgs e)

    {

        fv.ChangeMode(FormViewMode.Edit);

        bind();

    }

    protected void btnupdate_Click(object sender, EventArgs e)

    {

        DataRow[] dr;

        dr = dt.Select("sid="+((Label)fv.FindControl("lblid")).Text);

        dr[0][1] = ((TextBox)fv.FindControl("txtname")).Text;

        dr[0][2] = ((TextBox)fv.FindControl("txtmarks")).Text;

        da.Update(dt);

        fv.ChangeMode(FormViewMode.ReadOnly);

        bind();

    }

    protected void btncancle_Click(object sender, EventArgs e)

    {

        fv.ChangeMode(FormViewMode.ReadOnly);

        bind();

    }

    protected void btndelete_Click(object sender, EventArgs e)

    {

        DataRow[] dr;

        dr = dt.Select("sid="+((Label)fv.FindControl("lblid")).Text);

        dr[0].Delete();

        da.Update(dt);

        bind();

    }

    protected void btninsert_Click(object sender, EventArgs e)

    {

        int max=0;

        for (int i = 0; i < fv.PageCount; i++)

        {

            fv.PageIndex = i;

            bind();

            int h =Convert.ToInt32(((Label)fv.FindControl("lblid")).Text);

            if(max<h)

            {

             max = h;

            }

        }

        DataRow dr;

        dr = dt.Rows.Add();

        fv.PageIndex = fv.PageCount;

        bind();

        dr[0] = max + 1;

        fv.ChangeMode(FormViewMode.Edit);

        bind();

        da.Update(dt);      

      

    }

  

}

How to Bind Data in Datalist

Here,aspx  page  design

<div>
        <asp:DataList ID="dl" runat="server">
            <HeaderTemplate>
                <table>
                    <tr>
                        <td width="100px">
                            Id:
                        </td>
                        <td width="100px">
                            Name:
                        </td>
                        <td width="100px">
                            Marks:
                        </td>
                    </tr>
                </table>
            </HeaderTemplate>
            <ItemTemplate>
                <table>
                    <tr>
                        <td width="100px">
                            <asp:Label ID="lblid" runat="server" Text='<%#Eval("sid") %>'></asp:Label>
                        </td>
                        <td width="100px">
                            <asp:Label ID="lblname" runat="server" Text='<%#Eval("sname") %>'></asp:Label>
                        </td>
                        <td width="100px">
                            <asp:Label ID="lblmarks" runat="server" Text='<%#Eval("marks") %>'></asp:Label>
                        </td>
                    </tr>
                </table>
            </ItemTemplate>
        </asp:DataList>
    </div>

Now add the following namespaces in codebehind and After that write the following code

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data;
using System.Data.SqlClient;

public partial class _Default : System.Web.UI.Page 
{
     static SqlConnection con = new SqlConnection("Data Source=\\SQLEXPRESS;Initial Catalog;Integrated Security=True;Pooling=False");
     static SqlDataAdapter da = new SqlDataAdapter("select *from student",con);
     SqlCommandBuilder cmdb = new SqlCommandBuilder(da);
     DataTable dt = new DataTable();
       
    protected void Page_Load(object sender, EventArgs e)
    {
        if (Page.IsPostBack == false)
        {
            da.Fill(dt);
            ViewState["dt"] = dt;
            bind();
        }
        else
        {
            dt = (DataTable)ViewState["dt"];
        }
    }

    protected void bind()
    {        
        dl.DataSource = dt;
        dl.DataBind();     
    }

Create cookie in c#

Here simple code for createing cookie and value show on button click..!!

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
{
    HttpCookie mycookie = new HttpCookie("malvik");
    protected void Page_Load(object sender, EventArgs e)
    {
        if (Request.Cookies["malvik"] != null)
        {
         
            Response.Write(Request.Cookies["malvik"].Value);
        }
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        mycookie.Value = TextBox1.Text;
        mycookie.Expires = DateTime.Now.AddMinutes(1);
        Response.Cookies.Add(mycookie);
   
    }
    protected void btn1_Click(object sender, EventArgs e)
    {
        Page.Theme = "Theme1";
    }
}

Bind Data Into DropDownLIst

SqlConnection con = new SqlConnection("ConnectionString");
SqlDataAdapter da = new SqlDataAdapter("Select * from TableName",con);
DataTable dt = new DataTable();
da.Fill(dt);

ddlcategory.DataSource = dt;
ddlcategory.DataTextField = "Name";
ddlcategory.DataValueField = "Id";
ddlcategory.DataBind();
ddlcategory.Items.Insert(0, "---select---");

3 tier architecture example in asp.net with C#

Here I will how to create or implement 3-tier architecture for our project in asp.net 

Basically 3-Tier architecture contains 3 layers

1.    Property Layer 

2.    Business Logic Layer(BLL) 

3.    Data Access Layer(DAL)

Here I will explain each layer with simple example that is MangeCategory page

Bind DataTable Data In GridView

Here I will Explain how to bind Datatable data into gridview

First we take one gridview in the aspx page. in this gridview we bind student table data.it has three column sid,sname,marks.
Aspx page

<asp:GridView ID="gv" runat="server" AutoGenerateColumns="False"
            BackColor="White" BorderColor="#999999" BorderStyle="None" BorderWidth="1px"
            CellPadding="3" GridLines="Vertical" >      
            <AlternatingRowStyle BackColor="#DCDCDC" />
            <Columns>        
                <asp:BoundField DataField="sid" HeaderText="Id" ReadOnly="True" />
                <asp:BoundField DataField="sname" HeaderText="Name" />
                <asp:BoundField DataField="marks" HeaderText="Marks" />
                <asp:CommandField ShowEditButton="True" />
                <asp:CommandField ShowDeleteButton="True" />
            </Columns>        
        </asp:GridView>

Now add following namespaces in codebehind
Aspx.cs Page

using System.Data;
using System.Data.SqlClient;

After that add following code in code behind

 static SqlConnection con = new SqlConnection("Data Source=MALVIK-PC\\SQLEXPRESS;Initial Catalog=malvik;Integrated Security=True;Pooling=False");

    static SqlDataAdapter da = new SqlDataAdapter("select *from student", con);

    DataTable dt = new DataTable();

 protected void Page_Load(object sender, EventArgs e)

    {

        if (Page.IsPostBack == false)

        {

            da.Fill(dt);

            ViewState["dt"] = dt;

            bind();

        }

        else

        {

            dt = (DataTable)ViewState["dt"];

        }

    }

    protected void bind()

    {

        gv.DataSource = dt;

        gv.DataBind();

    }

Using StreamReader To Read HTML File/TextFile

Here I will explain how to read text or html file using StreamReader
In previous articles I explained write a html file using StreamWriter,now I will explain how to read text or html file using StreamReader.
we need to write the following code in aspx page

<asp:Button ID="btnread" runat="server" Text="Read" onclick="btnread_Click" />      

Now in code behind add the following namespaces          

using System;
using System.Collections.Generic;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
    }
    protected void btnread_Click(object sender, EventArgs e)
    {
        StreamReader sr = new StreamReader(Request.PhysicalApplicationPath + "nam_email.htm");
        while (sr.Peek() >= 0)
        {
            Response.Write(sr.ReadLine() + "<br />");
        }
        sr.Close();
    }
}