GridViewImages from DB in ASP.NET using C#

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.Data.SqlClient;
using System.IO;

public partial class _Default : System.Web.UI.Page 
{
    protected void Page_Load(object sender, EventArgs e)
    {

    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        if (FileUpload1.PostedFile != null && FileUpload1.PostedFile.FileName != "")
        {


            byte[] myimage = new byte[FileUpload1.PostedFile.ContentLength];
            HttpPostedFile Image = FileUpload1.PostedFile;
            Image.InputStream.Read(myimage, 0, (int)FileUpload1.PostedFile.ContentLength);

            SqlConnection myConnection = new SqlConnection("Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|\\Database.mdf;Integrated Security=True;User Instance=True");
            SqlCommand storeimage = new SqlCommand("INSERT INTO ImageGallery " + "(Image_Content, Image_Type, Image_Size) " + " values (@image, @imagetype, @imagesize)", myConnection);
            storeimage.Parameters.Add("@image", SqlDbType.Image, myimage.Length).Value = myimage;
            storeimage.Parameters.Add("@imagetype", SqlDbType.VarChar, 100).Value = FileUpload1.PostedFile.ContentType;
            storeimage.Parameters.Add("@imagesize", SqlDbType.BigInt, 99999).Value = FileUpload1.PostedFile.ContentLength;

            myConnection.Open();
            storeimage.ExecuteNonQuery();
            myConnection.Close();
        }

    }
    protected void LinkButton1_Click(object sender, EventArgs e)
    {
        GridView1.DataSource = FetchAllImagesInfo();
        GridView1.DataBind();
    }
    public DataTable FetchAllImagesInfo()
    {
        string sql = "Select * from ImageGallery";
        SqlDataAdapter da = new SqlDataAdapter(sql, "Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|\\Database.mdf;Integrated Security=True;User Instance=True");
        DataTable dt = new DataTable();
        da.Fill(dt);
        return dt;
    }
}