Hi

I want to send checkbox checked value to next page and display in a gridview. I only get a single value even if the multiple checkboxes are checked.

  <asp:GridView ID="GridView1" CssClass="table table-responsive table-striped" runat="server" CellPadding="3" BackColor="White" BorderColor="#CCCCCC" BorderStyle="None" BorderWidth="1px" >
      <Columns>
          <asp:TemplateField>
               <EditItemTemplate>
                    <asp:CheckBox ID="CheckBox1" runat="server" />
                   </EditItemTemplate>
              <ItemTemplate> 
                  <asp:CheckBox ID="CheckBox1" runat="server" />
          </ItemTemplate> 
              </asp:TemplateField>
          <asp:TemplateField>
               <ItemTemplate>
                   <a href="#" onclick='openPopup("<%# Eval("fig_Item_No")%>","<%# Eval("Part_number")%>","<%#Convert.ToBase64String((byte[])Eval("Image"))%>","<%# Eval("Vendor_Code")%>")'>Details</a>
              </ItemTemplate>
              </asp:TemplateField>
          <asp:TemplateField>
              <ItemTemplate>
                   <asp:Image ID="Image1" Width="150px" Height="50px" runat="server" ImageUrl='<%#"data:Image/jpg;base64," + Convert.ToBase64String((byte[])Eval("Image")) %>' />
              </ItemTemplate>
          </asp:TemplateField>
      </Columns>
      <FooterStyle BackColor="White" ForeColor="#000066" />
      <HeaderStyle BackColor="#006699" Font-Bold="True" ForeColor="White" />
      <PagerStyle ForeColor="#000066" HorizontalAlign="Left" BackColor="White" />
      <RowStyle ForeColor="#000066" />
      <SelectedRowStyle BackColor="#669999" Font-Bold="True" ForeColor="White" />
      <SortedAscendingCellStyle BackColor="#F1F1F1" />
      <SortedAscendingHeaderStyle BackColor="#007DBB" />
      <SortedDescendingCellStyle BackColor="#CAC9C9" />
      <SortedDescendingHeaderStyle BackColor="#00547E" />
  </asp:GridView> 
  <!--/.Card-->
  <br />
  <asp:Button ID="btnadd" OnClick="btnadd_Click" CssClass="btn btn-success ml-3" runat="server" Text="Add To Cart" Width="400px" />

protected void btnadd_Click(object sender, EventArgs e)
{
    SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["connString"].ConnectionString);
    StringBuilder strb = new StringBuilder();
    foreach(GridViewRow row in GridView1.Rows)
      {
        if (row.RowType == DataControlRowType.DataRow)
        {
            bool isChecked = (row.FindControl("CheckBox1") as CheckBox).Checked;
            if (isChecked)
            {
                // strb.Append(GridView1.Rows[i].Cells[7].Text ).AppendLine();
                strb.Append(GridView1.Rows[0].Cells[9].Text).AppendLine();
            }
        }               
    }
 
    // Session["vendor"] = strb.ToString();
    Session["vendor"] = strb.ToString().Trim('\n');
    Response.Redirect("order.aspx");
}

order.aspx

if (!this.IsPostBack)
{
    if (Session["vendor"] != null)
    {
        GetGridviewData();
    }
}
 
public void GetGridviewData()
{
    string[] vendors = Session["vendor"].ToString().Split('\n');
    foreach (string vendor in vendors)
    {
        var data = vendor.Trim();
        SqlConnection conn = new SqlConnection(ConfigurationManager.ConnectionStrings["connString"].ConnectionString);
        SqlCommand cmd = new SqlCommand("select Id,[Part_number],Nomenclature,[Vendor_Code],quantity,[quantity_available],[unit_price] from Catalouge where [Vendor_Code]=('" + data + "')", conn);
        Gridorder.DataSource = this.ExecuteQuery(cmd, "SELECT");
        Gridorder.DataBind();
    }
}
 
private DataTable ExecuteQuery(SqlCommand cmd, string action)
{
    string conString = (ConfigurationManager.ConnectionStrings["connString"].ConnectionString);
    using (SqlConnection con = new SqlConnection(conString))
    {
        cmd.Connection = con;
        switch (action)
        {
            case "SELECT":
                using (SqlDataAdapter sda = new SqlDataAdapter(cmd))
                {
                    sda.SelectCommand = cmd;
                    using (DataTable dt = new DataTable())
                    {
                        sda.Fill(dt);
                        return dt;
                    }
 
                }
            case "UPDATE":
                con.Open();
                cmd.ExecuteNonQuery();
                con.Close();
                break;
        }
        return null;
    }
}