On click event i want to play local video ..popup

i saved videos in local folder nw what my question is i want to play each video in grid i given linkbutton ..if user click on link button that related video pop and.. play (i did in you tube videos but nw i want to play local videos which are saved in local folder )..plz give me quick respons,...

LinkButton lnkView2 = (LinkButton)(sender);

HtmlControl contentPanel1 = (HtmlControl)pnlPopup.FindControl("youtubeIframe");

DataTable dt = GetRecords(dbFilePath);

int WebSiteLinkId = 0;

int ID = 0;

bool IsDownloaded = false;

string VTitle = "";

string videomp4 = "";

string root = @"D:\Dropbox\Dropbox\YouTube Videos\SVBS";

lblSubHeading.Text = videomp4;

for (int i = 0; i < dt.Rows.Count; i++)

{

VTitle = dt.Rows[i][6].ToString();

string illegal = VTitle;

string regexSearch = new string(Path.GetInvalidFileNameChars()) + new string(Path.GetInvalidPathChars());

Regex r = new Regex(string.Format("[{0}]", Regex.Escape(regexSearch)));

illegal = r.Replace(illegal, "");

videomp4 = illegal + ".mp4";

string subdirectroymp4file = @"D:\Dropbox\Dropbox\YouTube Videos\SVBS\" + videomp4;

if (videomp4 == subdirectroymp4file)

{

contentPanel1.Attributes["src"] = videomp4;

ModalPopupExtender1.Show();

}