delete row from grideview without SQLdataSource

html code

<%@ Page Language="C#" MasterPageFile="~/cpanel.master" AutoEventWireup="true" CodeFile="main_store.aspx.cs" Inherits="Edit_User" Title="Untitled Page" %>

<%@ Register assembly="AjaxControlToolkit" namespace="AjaxControlToolkit" tagprefix="cc1" %>

<asp:Content ID="Content1" ContentPlaceHolderID="head" Runat="Server">
    <style type="text/css">
        .style32
        {
            height: 32px;
        }
        .style33
        {
            width: 463px;
        }
        .style34
        {
            width: 463px;
            font-weight: bold;
        }
    </style>
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">

    <asp:ScriptManager ID="ScriptManager1" runat="server">
    </asp:ScriptManager>

    <center  style="background-color: #EEEEEE">
   
    <table  frame="box" style="width: 100%">
    <tr>
        <td align="left" bgcolor="Tan">
            
            BarCode
            
            <asp:TextBox ID="TextBox1" runat="server" Height="21px" 
               onkeypress="IsEnterKey(this)"  Width="309px" AutoPostBack="True" 
                ontextchanged="TextBox1_TextChanged1"></asp:TextBox>
                        
        </td>
        <td align="left" bgcolor="Tan">
            
            Category 
            
            <asp:DropDownList ID="item_supply" runat="server" AutoPostBack="True" 
                DataSourceID="SqlDataSource2" DataTextField="cat_name" DataValueField="cat_id" 
                ondatabound="item_supply_DataBound" Height="25px" style="margin-left: 0px" 
                Width="300px">
            </asp:DropDownList>
                        
        </td>
    </tr>
    <tr>
        <td align="center" colspan="2">
            
            <br />
            <asp:GridView ID="GridView1" runat="server" AllowPaging="True" 
                AutoGenerateColumns="False" BackColor="LightGoldenrodYellow" BorderColor="Tan" 
                BorderWidth="1px" CellPadding="2" DataKeyNames="code" 
                DataSourceID="SqlDataSource1" ForeColor="Black" GridLines="None" 
                Width="100%" ShowHeaderWhenEmpty="True">
                <AlternatingRowStyle BackColor="PaleGoldenrod" />
                <Columns>
                    <asp:CommandField ShowSelectButton="True" />
                    <asp:BoundField DataField="code" HeaderText="code" ReadOnly="True" 
                        SortExpression="code" />
                    <asp:BoundField DataField="item_name" HeaderText="item_name" 
                        SortExpression="item_name" />
                    <asp:BoundField DataField="item_desc" HeaderText="item_desc" 
                        SortExpression="item_desc" />
                    <asp:BoundField DataField="item_min" HeaderText="item_min" 
                        SortExpression="item_min" />
                    <asp:BoundField DataField="item_max" HeaderText="item_max" 
                        SortExpression="item_max" />
                    <asp:BoundField DataField="item_supply" HeaderText="item_supply" 
                        SortExpression="item_supply" />
                    <asp:BoundField DataField="item_price" HeaderText="item_price" 
                        SortExpression="item_price" />
                    <asp:BoundField DataField="item_cat" HeaderText="item_cat" 
                        SortExpression="item_cat" />
                </Columns>
                <FooterStyle BackColor="Tan" />
                <HeaderStyle BackColor="Tan" Font-Bold="True" />
                <PagerStyle BackColor="PaleGoldenrod" ForeColor="DarkSlateBlue" 
                    HorizontalAlign="Center" />
                <SelectedRowStyle BackColor="DarkSlateBlue" ForeColor="GhostWhite" />
                <SortedAscendingCellStyle BackColor="#FAFAE7" />
                <SortedAscendingHeaderStyle BackColor="#DAC09E" />
                <SortedDescendingCellStyle BackColor="#E1DB9C" />
                <SortedDescendingHeaderStyle BackColor="#C2A47B" />
            </asp:GridView>
            <asp:SqlDataSource ID="SqlDataSource1" runat="server" 
                ConnectionString="<%$ ConnectionStrings:myconstr %>" 
                
                
                SelectCommand="SELECT code, item_name, item_desc, item_min, item_max, item_supply, item_price, item_cat FROM Items WHERE (item_name LIKE '%' + @name + '%'  ) AND ((item_cat = @cat) OR (@cat = 0))">
                <SelectParameters>
                    <asp:ControlParameter ControlID="TextBox1" DefaultValue="" Name="name" 
                        PropertyName="Text" />
                    <asp:ControlParameter ControlID="item_supply" Name="cat" 
                        PropertyName="SelectedValue" />
                </SelectParameters>
            </asp:SqlDataSource>
            
        &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
            &nbsp;&nbsp;
                        
            <br />
            <br />
                        
            <asp:SqlDataSource ID="SqlDataSource2" runat="server" 
                ConnectionString="<%$ ConnectionStrings:myconstr %>" 
                SelectCommand="SELECT * FROM [cat]"></asp:SqlDataSource>
                        
        </td>
    </tr>
    </table>
        <table width="100%">
            <tr>
                <td align="left" bgcolor="Tan" class="style34">
                    Invoice Information</td>
            </tr>
            <tr>
                <td align="left" bgcolor="Tan" class="style33">
                    Invoice No
                    <asp:TextBox ID="inv_no" runat="server"></asp:TextBox>
&nbsp; Invoice Date
                    <asp:TextBox ID="inv_date" runat="server" Height="24px" Width="150px"></asp:TextBox>
                    <cc1:CalendarExtender ID="inv_date_CalendarExtender" runat="server" 
                        Enabled="True" TargetControlID="inv_date" Format="dd/MM/yyyy">
                    </cc1:CalendarExtender>
                </td>
                <td align="left" bgcolor="Tan">
                    Supplier
                    <asp:DropDownList ID="supply" runat="server" 
                        DataSourceID="SqlDataSource3" DataTextField="supplier_name" 
                        DataValueField="code" Height="16px" Width="158px">
                    </asp:DropDownList>
                    <asp:SqlDataSource ID="SqlDataSource3" runat="server" 
                        ConnectionString="<%$ ConnectionStrings:myconstr %>" 
                        SelectCommand="SELECT [supplier_name], [code] FROM [suppliers]">
                    </asp:SqlDataSource>
                </td>
            </tr>
            <tr>
                <td align="left" bgcolor="LightGoldenrodYellow" class="style33">
                    &nbsp;</td>
                <td align="left" bgcolor="LightGoldenrodYellow">
                    &nbsp;</td>
            </tr>
            <tr>
                <td align="left" bgcolor="Tan" class="style33">
                    BrCode
                    <asp:TextBox ID="code" runat="server" Height="26px" Width="364px" 
                        AutoPostBack="True" ontextchanged="code_TextChanged"></asp:TextBox>
                </td>
                <td align="left" bgcolor="Tan">
                    Quntity
                    <asp:TextBox ID="qun" runat="server" AutoPostBack="True" 
                        ontextchanged="qun_TextChanged" Height="27px" Width="300px"></asp:TextBox>
                    <cc1:FilteredTextBoxExtender ID="qun_FilteredTextBoxExtender" runat="server" 
                        Enabled="True" FilterType="Numbers" TargetControlID="qun">
                    </cc1:FilteredTextBoxExtender>
                </td>
            </tr>
            <tr>
                <td align="left" class="style33" bgcolor="LightGoldenrodYellow">
                    <b>Item Name :</b><asp:Label ID="lblname" runat="server"></asp:Label>
                </td>
                <td align="left" bgcolor="LightGoldenrodYellow">
                    <b>Item Quntity :</b><asp:Label ID="lblqun" runat="server"></asp:Label>
                </td>
            </tr>
            <tr>
                <td class="style32" colspan="2">
                    <asp:GridView ID="GridView2" runat="server" 
                        BackColor="LightGoldenrodYellow" BorderColor="Tan" BorderWidth="1px" 
                        CellPadding="2" ForeColor="Black" GridLines="None" 
                        AutoGenerateDeleteButton="True" onrowdeleting="GridView2_RowDeleting" 
                        Width="100%" ShowFooter="True" ShowHeaderWhenEmpty="True">
                        <AlternatingRowStyle BackColor="PaleGoldenrod" />
                        <FooterStyle BackColor="Tan" />
                        <HeaderStyle BackColor="Tan" Font-Bold="True" HorizontalAlign="Left" 
                            VerticalAlign="Middle" />
                        <PagerStyle BackColor="PaleGoldenrod" ForeColor="DarkSlateBlue" 
                            HorizontalAlign="Center" />
                        <RowStyle HorizontalAlign="Left" VerticalAlign="Middle" />
                        <SelectedRowStyle BackColor="DarkSlateBlue" ForeColor="GhostWhite" />
                        <SortedAscendingCellStyle BackColor="#FAFAE7" />
                        <SortedAscendingHeaderStyle BackColor="#DAC09E" />
                        <SortedDescendingCellStyle BackColor="#E1DB9C" />
                        <SortedDescendingHeaderStyle BackColor="#C2A47B" />
                           <Columns>
                              <asp:CommandField ShowDeleteButton="True" ButtonType="Button" />
                           </Columns>
                                        
                    </asp:GridView>
   

                </td>
            </tr>
            <tr>
                <td class="style33" align="left">
                    <asp:Button ID="Button1" runat="server" onclick="Button1_Click" 
                        Text="ادخال للمستودع" />
                </td>
                <td>
                    &nbsp;</td>
            </tr>
            <tr>
                <td class="style33" align="left">
                    <asp:Label ID="lblmsg" runat="server"></asp:Label>
                </td>
                <td>
                    &nbsp;</td>
            </tr>
        </table>
        <asp:SqlDataSource ID="SqlDataSource4" runat="server" 
            ConnectionString="<%$ ConnectionStrings:myconstr %>" 
            DeleteCommand="DELETE FROM [invoices] WHERE [serials] = @serials" 
            InsertCommand="INSERT INTO [invoices] ([Invoice_no], [Invoice_Date], [Supplier]) VALUES (@Invoice_no, @Invoice_Date, @Supplier)" 
            SelectCommand="SELECT * FROM [invoices]" 
            UpdateCommand="UPDATE [invoices] SET [Invoice_no] = @Invoice_no, [Invoice_Date] = @Invoice_Date, [Supplier] = @Supplier, [amount] = @amount WHERE [serials] = @serials">
            <DeleteParameters>
                <asp:Parameter Name="serials" Type="Int32" />
            </DeleteParameters>
            <InsertParameters>
                <asp:ControlParameter ControlID="inv_no" Name="Invoice_no" PropertyName="Text" 
                    Type="String" />
                <asp:ControlParameter ControlID="inv_date" Name="Invoice_Date" 
                    PropertyName="Text" Type="DateTime" />
                <asp:ControlParameter ControlID="supply" Name="Supplier" 
                    PropertyName="SelectedValue" Type="Int32" />
            </InsertParameters>
            <UpdateParameters>
                <asp:Parameter Name="Invoice_no" Type="String" />
                <asp:Parameter Name="Invoice_Date" Type="DateTime" />
                <asp:Parameter Name="Supplier" Type="Int32" />
                <asp:Parameter Name="amount" Type="Double" />
                <asp:Parameter Name="serials" Type="Int32" />
            </UpdateParameters>
        </asp:SqlDataSource>
        <asp:SqlDataSource ID="SqlDataSource5" runat="server" 
            ConnectionString="<%$ ConnectionStrings:myconstr %>" 
            DeleteCommand="DELETE FROM [purchasing] WHERE [serial] = @serial" 
            InsertCommand="INSERT INTO [purchasing] ([invoice_no_fk], [item_code_fk], [item_price], [serial]) VALUES (@invoice_no_fk, @item_code_fk, @item_price, @serial)" 
            SelectCommand="SELECT [invoice_no_fk], [item_code_fk], [item_price], [serial] FROM [purchasing]" 
            UpdateCommand="UPDATE [purchasing] SET [invoice_no_fk] = @invoice_no_fk, [item_code_fk] = @item_code_fk, [item_price] = @item_price WHERE [serial] = @serial">
            <DeleteParameters>
                <asp:Parameter Name="serial" Type="Int32" />
            </DeleteParameters>
            <InsertParameters>
                <asp:Parameter Name="invoice_no_fk" Type="String" />
                <asp:Parameter Name="item_code_fk" Type="Int32" />
                <asp:Parameter Name="item_price" Type="Double" />
                <asp:Parameter Name="serial" Type="Int32" />
            </InsertParameters>
            <UpdateParameters>
                <asp:Parameter Name="invoice_no_fk" Type="String" />
                <asp:Parameter Name="item_code_fk" Type="Int32" />
                <asp:Parameter Name="item_price" Type="Double" />
                <asp:Parameter Name="serial" Type="Int32" />
            </UpdateParameters>
        </asp:SqlDataSource>
    <br/>
    </center>
</asp:Content>

cs code

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;

public partial class Edit_User : System.Web.UI.Page
{
    string cs = ConfigurationManager.ConnectionStrings["myconstr"].ConnectionString.ToString();
    DataTable dt = new DataTable();


    protected void Page_Load(object sender, EventArgs e)
    {
        

    }


    void ShowData()
    {
        SqlConnection cn = new SqlConnection(cs);
        cn.Open();
        string sqlSelect = "Select item_name , code_fk , item_qun  from items,main_store where code=code_fk and  code=" + code.Text + "";
        SqlCommand cmd = new SqlCommand();
        cmd.Connection = cn;
        cmd.CommandType = CommandType.Text;
        cmd.CommandText = sqlSelect;
        SqlDataReader dr;

        dr = cmd.ExecuteReader();

        if (dr.Read())
        {
            lblname.ForeColor = System.Drawing.Color.Green;
            lblname.Text = (dr["item_name"]).ToString();
            lblqun.Text = (dr["item_qun"]).ToString();
            qun.Focus();

     

        }
        else
        {
            lblname.ForeColor = System.Drawing.Color.Red;
            lblname.Text = "No Matched BarCode";
            code.Focus();
        }
        cn.Close();

    }


    //void del_user()
    //{
    //    SqlConnection cn = new SqlConnection(cs);
    //    cn.Open();
    //    string sqlSelect = "delete  from User_Info where User_Id_Pk=" + User_Select.SelectedValue + "";
    //    SqlCommand cmd = new SqlCommand();
    //    cmd.Connection = cn;
    //    cmd.CommandType = CommandType.Text;
    //    cmd.CommandText = sqlSelect;
    //    SqlDataReader dr;
    //    dr = cmd.ExecuteReader();
    //    lblMsg.Text = "تم الحذف بنجاح";
    //    cn.Close();
    //}


   



    //void updateUser()
    //{
    //    SqlConnection cn = new SqlConnection(cs);
    //    cn.Open();
    //    SqlCommand cmd = new SqlCommand();
    //    string sqlStatment = " update [User_Info] set Emp_Name=@Emp_Name,User_Name=@User_Name,User_Password=@User_Password,User_Type=@User_Type,User_Stats=@User_Stats,User_Commission=@User_Commission,User_Salary=@User_Salary" +
    //                 " where User_Id_PK=@User_Id_PKlbl ";
    //    cmd.CommandType = CommandType.Text;
    //    cmd.CommandText = sqlStatment;
    //    cmd.Connection = cn;
    //    cmd.Parameters.AddWithValue("@User_Id_PKlbl", User_Id_PKlbl.Text);
    //    cmd.Parameters.AddWithValue("@Emp_Name", EmpName.Text);
    //    cmd.Parameters.AddWithValue("@User_Name", UserName.Text);
    //    cmd.Parameters.AddWithValue("@User_Password", Password.Text);
    //    cmd.Parameters.AddWithValue("@User_Type", DropDownList1.SelectedValue);
    //    cmd.Parameters.AddWithValue("@User_Stats", DropDownList2.SelectedValue);
    //    cmd.Parameters.AddWithValue("@User_Commission", DropDownList3.SelectedValue);
    //    cmd.Parameters.AddWithValue("@User_Salary", empsalary.Text);
    //    SqlDataAdapter ad = new SqlDataAdapter(cmd);
    //    DataSet ds = new DataSet();
    //    ad.SelectCommand = cmd;
    //    ad.Fill(ds);
    //    lblMsg.Text = "تم تعديل البيانات";
    //    cn.Close();
    //}

    protected void item_supply_DataBound(object sender, EventArgs e)
    {
        ListItem li = new ListItem("-- Select Supplier --", "0");
        item_supply.Items.Insert(0, li);
    }
    protected void TextBox1_TextChanged(object sender, EventArgs e)
    {
        SqlDataSource1.DataBind();
    }

  
    protected void code_TextChanged(object sender, EventArgs e)
    {
         ShowData();
    }
    protected void code_Disposed(object sender, EventArgs e)
    {
        ShowData();
    }
    protected void TextBox1_TextChanged1(object sender, EventArgs e)
    {
        SqlDataSource1.DataBind();
    }
    protected void qun_TextChanged(object sender, EventArgs e)
    {
        if (lblmsg.Text == "No Matched BarCode")
        {

            code.Focus();
        }

        else
        {
            if (GridView2.Rows.Count == 0)
            {
                dt = MakeTable();

            }
            else
            {
                dt = (DataTable)ViewState["dt"];
            }
            DataRow dr = dt.NewRow();
            dr[0] = lblname.Text;
            dr[1] = code.Text;
            dr[2] = qun.Text;
            dt.Rows.Add(dr);
            GridView2.DataSource = null;
            GridView2.DataSource = dt;
            GridView2.DataBind();
            ViewState.Add("dt", dt);
            code.Text = "";
            code.Focus();
            qun.Text = "";
        }
    }
    DataTable MakeTable()
    {
        DataTable Mydt = new DataTable();
        DataColumn col1 = new DataColumn("Item Name");
        col1.DataType = System.Type.GetType("System.String");

        Mydt.Columns.Add(col1);

        DataColumn col2 = new DataColumn("Item Barcode");
        col1.DataType = System.Type.GetType("System.String");
        Mydt.Columns.Add(col2);


        DataColumn col3 = new DataColumn("Item Qun");
        col1.DataType = System.Type.GetType("System.String");
        Mydt.Columns.Add(col3);
        return Mydt;
    }



    protected void GridView2_RowDeleting(object sender, GridViewDeleteEventArgs e)
    {

        int index = Convert.ToInt32(e.RowIndex);
        DataTable dt = ViewState["dt"] as DataTable;
        dt.Rows[index].Delete();
        ViewState["dt"] = dt;
        



    }

    protected void Button1_Click(object sender, EventArgs e)
    {
        int done = 0;
        foreach (GridViewRow row in GridView2.Rows)
        {
            if (row.RowType == DataControlRowType.DataRow)
            {
               
                    done++;

                    SqlConnection cn = new SqlConnection(cs);
                    cn.Open();
                    SqlCommand cmd = new SqlCommand();

                    string sqlStatment = " update [main_store] set [item_qun] = [item_qun] + @qun where code_fk=@code1";
                                        
                                         
                                       
                    cmd.CommandType = CommandType.Text;
                    cmd.CommandText = sqlStatment;
                    cmd.Connection = cn;
                    cmd.Parameters.AddWithValue("@code1", (row.Cells[2].Text));
                    cmd.Parameters.AddWithValue("@code2", (row.Cells[2].Text));
                   cmd.Parameters.AddWithValue("@qun", (row.Cells[3].Text));
                   cmd.Parameters.AddWithValue("@invoice_no_fk", (inv_no.Text));
                    SqlDataAdapter ad = new SqlDataAdapter(cmd);
                    DataSet ds = new DataSet();
                    ad.SelectCommand = cmd;
                    ad.Fill(ds);
                    cn.Close();
                    GridView2.DataSource = null ;
                    GridView2.DataBind();
                    lblmsg.ForeColor = System.Drawing.Color.Green;
                    lblmsg.Text = "Saved To Main Store Succefully";


                }

            }
        SqlDataSource4.Insert();
        }
    }

Shashikant says:

Delete row from GridView without using database in ASP.Net

Insert data in GridView without using database in ASP.Net

Using DataTable as Temporary storage table in ASP.Net

I saw your code. You have not implemented the code properly. So Please go through the above articles step by step then try to implement the same in your code.

http://stackoverflow.com/questions/813168/how-to-delete-a-row-in-a-gridview-and-the-underlying-datasource-without-using-a 

http://www.c-sharpcorner.com/blogs/insert-update-and-delete-using-a-formview1