Update GridView Checked Rows data in database using C# in ASP.Net

Hi akhter,

Refer below code.

HTML

order No
<asp:TextBox ID="TextBox1" runat="server" AutoPostBack="True" OnTextChanged="TextBox1_TextChanged"></asp:TextBox>
<asp:Button ID="btnUpdate" runat="server" Text="Update" OnClick="Update" />
<div class="auto-style4">
    <asp:GridView ID="GVallbb" runat="server" BackColor="White" BorderColor="#E7E7FF"
        BorderStyle="None" BorderWidth="1px" CellPadding="3" GridLines="Horizontal" AutoGenerateColumns="false"
        Font-Names="Arial" CssClass="HeaderFreez" ShowHeader="true" Font-Size="11pt"
        AlternatingRowStyle-BackColor="#C2D69B" class="grid_scroll" PageSize="5" ShowHeaderWhenEmpty="True"
        DataKeyNames="BalNo" ShowFooter="True" Style="margin-right: 0px">
        <AlternatingRowStyle BackColor="#F7F7F7" />
        <FooterStyle BackColor="#B5C7DE" ForeColor="#4A3C8C" />
        <HeaderStyle BackColor="#4A3C8C" Font-Bold="True" ForeColor="#F7F7F7" />
        <PagerStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" HorizontalAlign="Right" />
        <RowStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" />
        <SelectedRowStyle BackColor="#738A9C" Font-Bold="True" ForeColor="#F7F7F7" />
        <SortedAscendingCellStyle BackColor="#F4F4FD" />
        <SortedAscendingHeaderStyle BackColor="#5A4C9D" />
        <SortedDescendingCellStyle BackColor="#D8D8F0" />
        <SortedDescendingHeaderStyle BackColor="#3E3277" />
        <Columns>
            <asp:TemplateField>
                <HeaderTemplate>
                    <asp:CheckBox ID="chkAll" runat="server" AutoPostBack="true" OnCheckedChanged="OnCheckedChanged" />
                </HeaderTemplate>
                <ItemTemplate>
                    <asp:CheckBox ID="CheckBox1" runat="server" AutoPostBack="true" OnCheckedChanged="OnCheckedChanged" />
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Bale No">
                <ItemTemplate>
                    <asp:HiddenField ID="hfBID" runat="server" Value='<%#Eval("BID")%>' />
                    <asp:Label ID="BalNo" runat="server" Text='<%#Bind("BalNo","{0:#,000}")%>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="OrderNo">
                <ItemTemplate>
                    <asp:Label ID="OrderNo" runat="server" Text='<%#Bind("OrderNo")%>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Item Name">
                <ItemTemplate>
                    <asp:Label ID="itemName" runat="server" Text='<%#Bind("Descriptionitem")%>'></asp:Label>
                </ItemTemplate>
                <FooterTemplate>
                    <asp:Label ID="lblTotalText" Text="Total" runat="server"></asp:Label></FooterTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="QTY">
                <ItemTemplate>
                    <asp:Label ID="itemQty" runat="server" Text='<%#Bind("QTY")%>'></asp:Label>
                </ItemTemplate>
                <FooterTemplate>
                    <asp:Label ID="lblTotal" runat="server"></asp:Label></FooterTemplate>
                <%--<FooterTemplate><asp:Label ID="lblTotalText" Text="Total" runat="server"></asp:Label></FooterTemplate>--%>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="BaleSize">
                <ItemTemplate>
                    <asp:Label ID="BaleSize" runat="server" Text='<%#Bind("BaleSize")%>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Ref_ID">
                <ItemTemplate>
                    <asp:Label ID="Ref_ID" runat="server" Text='<%#Bind("Ref_ID")%>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Worker">
                <ItemTemplate>
                    <asp:Label ID="worker" runat="server" Text='<%#Bind("worker")%>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Floor">
                <ItemTemplate>
                    <asp:Label ID="Floor" runat="server" Text='<%#Bind("Floor")%>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Section">
                <ItemTemplate>
                    <asp:Label ID="Section" runat="server" Text='<%#Bind("Section")%>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField HeaderText="Date">
                <ItemTemplate>
                    <asp:Label ID="EntryDate" runat="server" Text='<%#Bind("EntryDate","{0:MM/dd/yyyy}")%>'></asp:Label>
                </ItemTemplate>
            </asp:TemplateField>
        </Columns>
    </asp:GridView>
</div>

Code

protected void Update(object sender, EventArgs e)
{
    foreach (GridViewRow row in GVallbb.Rows)
    {
        if ((row.FindControl("CheckBox1") as CheckBox).Checked)
        {
            int bid = Convert.ToInt32((row.FindControl("hfBID") as HiddenField).Value);
            string conString = ConfigurationManager.ConnectionStrings["constr"].ConnectionString;
            string query = "UPDATE Probale SET Orderno = @OrderNumber WHERE BID = @BId";
            SqlCommand cmd = new SqlCommand(query);
            using (SqlConnection con = new SqlConnection(conString))
            {
                cmd.Connection = con;
                cmd.Parameters.AddWithValue("@BId", bid);
                cmd.Parameters.AddWithValue("@OrderNumber", TextBox1.Text);
                con.Open();
                cmd.ExecuteNonQuery();
                con.Close();
            }
        }
    }
}