Save and Download QR Code image in ASP.Net

Hi,

Please refer below code.

HTML

<div>
    <asp:TextBox ID="txtCode" runat="server"></asp:TextBox>
    <asp:Button ID="btnGenerate" runat="server" Text="Generate" OnClick="btnGenerate_Click" />
    <hr />
    <asp:PlaceHolder ID="plBarCode" runat="server" />
    <asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="false" EmptyDataText="No files uploaded">
        <Columns>
            <asp:BoundField DataField="Text" HeaderText="File Name" />
            <asp:TemplateField HeaderText="QRCode">
                <ItemTemplate>
                    <asp:Image ImageUrl='<%#Eval("Text","~/QRCodes/{0}") %>' runat="server" Width="100px"
                        Height="100px" />
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField>
                <ItemTemplate>
                    <asp:LinkButton ID="lnkDownload" Text="Download" CommandArgument='<%# Eval("Value") %>'
                        runat="server" OnClick="DownloadFile"></asp:LinkButton>
                </ItemTemplate>
            </asp:TemplateField>
            <asp:TemplateField>
                <ItemTemplate>
                    <asp:LinkButton ID="lnkDelete" Text="Delete" CommandArgument='<%# Eval("Value") %>'
                        runat="server" OnClick="DeleteFile" />
                </ItemTemplate>
            </asp:TemplateField>
        </Columns>
    </asp:GridView>
</div>

C#

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

private void BindGrid()
{
    string[] filePaths = Directory.GetFiles(Server.MapPath("~/QRCodes/"));
    List<ListItem> files = new List<ListItem>();
    foreach (string filePath in filePaths)
    {
        files.Add(new ListItem(Path.GetFileName(filePath), filePath));
    }
    GridView1.DataSource = files;
    GridView1.DataBind();
}

protected void btnGenerate_Click(object sender, EventArgs e)
{
    string code = txtCode.Text;
    if (!string.IsNullOrEmpty(code))
    {
        QRCodeGenerator qrGenerator = new QRCodeGenerator();
        QRCodeGenerator.QRCode qrCode = qrGenerator.CreateQrCode(code, QRCodeGenerator.ECCLevel.Q);
        System.Web.UI.WebControls.Image imgBarCode = new System.Web.UI.WebControls.Image();
        imgBarCode.Height = 150;
        imgBarCode.Width = 150;
        using (Bitmap bitMap = qrCode.GetGraphic(20))
        {
            using (MemoryStream ms = new MemoryStream())
            {
                bitMap.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
                byte[] byteImage = ms.ToArray();
                File.WriteAllBytes(Server.MapPath("QRCodes/" + txtCode.Text + ".png"), byteImage);
                //imgBarCode.ImageUrl = "data:image/png;base64," + Convert.ToBase64String(byteImage);
            }
            //plBarCode.Controls.Add(imgBarCode);
            BindGrid();
        }
    }
}

protected void DownloadFile(object sender, EventArgs e)
{
    string filePath = (sender as LinkButton).CommandArgument;
    Response.ContentType = ContentType;
    Response.AppendHeader("Content-Disposition", "attachment; filename=" + Path.GetFileName(filePath));
    Response.WriteFile(filePath);
    Response.End();
}

protected void DeleteFile(object sender, EventArgs e)
{
    string filePath = (sender as LinkButton).CommandArgument;
    File.Delete(filePath);
    Response.Redirect(Request.Url.AbsoluteUri);
}

Screenshot