How to display images in Image control from database in Asp.net C#?

here is the table structure

this the code I have used to load images

protected void btnshwimg_Click(object sender, EventArgs e)  
{   
    conn.Open();
    SqlCommand cmd = new SqlCommand("select CategoryLogo from Categories  
    where CategoryId = '" + ddlcategoryname.SelectedValue.ToString()+ "'",    conn);
    SqlDataReader reader = cmd.ExecuteReader();
    if (reader.Read())
    {
       byte[] picData = (byte[])reader["CategoryLogo"];
       string base64String = Convert.ToBase64String(picData, 0, picData.Length);
       Image1.ImageUrl = "data:image/png;base64," + base64String;
     }
    conn.Close();
}