Displaying Same images in gridview Based on dropdown selection

Menu Table
-------------------------------
MenuId MenuName 
-------------------------------
11      Shirts

Product Table 
---------------------------------------------
ProductId ProductName MenuId ProductImage
---------------------------------------------
1         Levisshirts  11     image
2         white shirt  11     image2

{
    con.Open();
    if (!IsPostBack)
        ddlbind();
}

private void BindGridData()
{
    SqlCommand command = new SqlCommand("SELECT * from rsa_ProductItemTable where  MenuId=" + Dropsearch.SelectedItem.Value, con);
    SqlDataAdapter daimages = new SqlDataAdapter(command);
    DataSet ds = new DataSet();
    daimages.Fill(ds);
    GridView1.DataSource = ds;
    GridView1.DataBind();
    GridView1.Attributes.Add("bordercolor", "black");
}

public void ddlbind()
{
    SqlCommand command = new SqlCommand("SELECT * from rsa_mastermenu", con);
    SqlDataAdapter daimages = new SqlDataAdapter(command);
    DataTable dt = new DataTable();
    daimages.Fill(dt);
    Dropsearch.DataSource = dt;
    Dropsearch.DataTextField = "MenuName";
    Dropsearch.DataValueField = "MenuId";
    Dropsearch.DataBind();
    Dropsearch.Items.Insert(0, new ListItem("Select", "0"));
}

protected void Dropsearch_SelectedIndexChanged(object sender, EventArgs e)
{
    int imgid = int.Parse(Dropsearch.SelectedItem.Value);
    BindGridData();
}

protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.DataRow)
    {
        Image img = (Image)e.Row.FindControl("Image1");
        img.ImageUrl = "GridviewImage.ashx?ImID=" + Dropsearch.SelectedItem.Value;
    }
}