when i click the Url in the list i want to open the url in new tab also login automatically.
If it's a Forms Authentication, pass the username & password as querystring in the URL.
Then, all you need to do in your page load is something like:
string username = Request.QueryString["username"].ToString();
string password = Request.QueryString["password"].ToString();
if (Membership.ValidateUser(username , password))
{
FormsAuthentication.SetAuthCookie(username , true);
Response.Redirect("~/");
}
Other way could be to use HttpWebReqest and HttpWebResponse, pass appropriate parameters of the page while crawling using code behind.
See these samples:
VBASPNETAutoLogin Overview[
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HttpWebRequest Post method[
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