Login from SQL-server in ASP.Net C#

    private bool SiteLevelCustomAuthenticationMethod(string UserName, string Password)
    {

        bool boolReturnValue = false;

        string strConnection = ConnectionString;

        SqlConnection Connection = new SqlConnection(strConnection);
        string strUserID = UserName;
        String strSQL = "select * from UserDetails where UDUSRID=\'" + (strUserID + "\'");
        SqlCommand command = new SqlCommand(strSQL, Connection);
        SqlDataReader Dr;
        Connection.Open();
        Dr = command.ExecuteReader();
        while (Dr.Read())
        {
            string UserNameDB = Dr["UDUSRID"].ToString();
            string PasswordDB = Dr["UDPASSWD"].ToString();
            //  string UserRoleDB = Dr["UDROLE"].ToString();


            if ((UserName == UserNameDB.TrimEnd().TrimStart()) & (Password == PasswordDB.TrimEnd().TrimStart()))
            {
                Session["Usrid"] = UserNameDB;
                Session["Uspasswd"] = PasswordDB;
                //    Session["Usrole"] = UserRoleDB;
                //  Response.Write(Session["Usrole"]);
                // Response.End();

                boolReturnValue = true;
                break;

            }

        }

        Dr.Close();

        return boolReturnValue;

    }