How to update binary image files stored in database using GridView in ASP.Net

HTML

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" OnRowDataBound = "OnRowDataBound" OnRowEditing="OnRowEditing" OnRowCancelingEdit = "OnRowCancelEdit" OnRowUpdating = "OnRowUpdating">
    <Columns>
        <asp:BoundField DataField="ID" HeaderText="ID" ReadOnly="true" />
        <asp:BoundField DataField="Name" HeaderText="Name" ReadOnly="true" />
        <asp:TemplateField>
            <ItemTemplate>
                <asp:Image ID="Image1" Height="100" Width="100" runat="server" />
            </ItemTemplate>
            <EditItemTemplate>
                <asp:FileUpload ID="fuImage" runat="server" />
            </EditItemTemplate>
        </asp:TemplateField>
        <asp:CommandField ShowEditButton="true" />
    </Columns>
</asp:GridView>

Namespaces

using System.IO;
using System.Data;
using System.Configuration;
using System.Data.SqlClient;

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        this.BindGrid();
    }
}

private void BindGrid()
{
    string constr = ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
    using (SqlConnection con = new SqlConnection(constr))
    {
        using (SqlCommand cmd = new SqlCommand("SELECT ID, Name, Data FROM tblFiles ORDER BY ID"))
        {
            cmd.Connection = con;
            using (SqlDataAdapter sda = new SqlDataAdapter())
            {
                DataTable dt = new DataTable();
                sda.SelectCommand = cmd;
                sda.Fill(dt);
                GridView1.DataSource = dt;
                GridView1.DataBind();
            }
        }
    }
}

protected void OnRowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow && GridView1.EditIndex != e.Row.RowIndex)
    {
        byte[] bytes = (byte[])DataBinder.Eval(e.Row.DataItem, "Data");
        string base64String = Convert.ToBase64String(bytes, 0, bytes.Length);
        (e.Row.FindControl("Image1") as Image).ImageUrl = "data:image/png;base64," + base64String;
    }
}

protected void OnRowEditing(object sender, GridViewEditEventArgs e)
{
    GridView1.EditIndex = e.NewEditIndex;
    this.BindGrid();
}

protected void OnRowCancelEdit(object sender, GridViewCancelEditEventArgs e)
{
    GridView1.EditIndex = -1;
    this.BindGrid();
}

protected void OnRowUpdating(object sender, GridViewUpdateEventArgs e)
{
    GridViewRow row = GridView1.Rows[e.RowIndex];
    int id = int.Parse(row.Cells[0].Text);
    FileUpload fuImage = row.FindControl("fuImage") as FileUpload;
    string name = Path.GetFileName(fuImage.PostedFile.FileName);
    using (Stream fs = fuImage.PostedFile.InputStream)
    {
        using (BinaryReader br = new BinaryReader(fs))
        {
            byte[] bytes = br.ReadBytes((Int32)fs.Length);
            string constr = ConfigurationManager.ConnectionStrings["conString"].ConnectionString;
            using (SqlConnection con = new SqlConnection(constr))
            {
                using (SqlCommand cmd = new SqlCommand("UPDATE tblFiles SET Name = @Name, ContentType = @ContentType, Data = @Data WHERE ID = @Id"))
                {
                    cmd.Parameters.AddWithValue("@ID", id);
                    cmd.Parameters.AddWithValue("@Name", name);
                    cmd.Parameters.AddWithValue("@ContentType", fuImage.PostedFile.ContentType);
                    cmd.Parameters.AddWithValue("@Data", bytes);

                    cmd.Connection = con;
                    con.Open();
                    cmd.ExecuteNonQuery();
                    con.Close();
                }
            }
        }
    }
    GridView1.EditIndex = -1;
    this.BindGrid();
}