C # WinForm Implementation remembers login status for user login

namespace dms{public    class Logininfo    {public        string AccountID        {            set;            get;        }        public string Accountpassword        {            set;            get;                    }        Public DateTime accountlogintime        {            set;                       get;                    }        private static Logininfo _currentuser = null;        public static Logininfo CurrentUser        {            get            {                if (_currentuser = = null)                {                    _currentuser = New Logininfo ();                }                return _currentuser;}}}    

Seems to be called single-piece mode (Singleton) ... Anyway finish this course design and take a good look at the design pattern of things (escape

namespace dms{public partial class login interface: Form {public Login interface () {InitializeComponent (); private void Buttonadmin_click (object sender, EventArgs e) {if (TextBoxUserName.Text.Trim () != "" ||                TextBoxPassWord.Text.Trim ()! = "") {//Connect database for comparison ...//prepare try//to start {Conn.                    Open (); SqlDataReader reader = cmd.                    ExecuteReader (); Reader.                    Read (); if (reader. HasRows)//Existing account {/* Below four lines is the key */LoginInfo.CurrentUser.Accoun                        TID = TextBoxUserName.Text.Trim ();                        LoginInfo.CurrentUser.AccountPassWord = TextBoxPassWord.Text.Trim ();                        LoginInfo.CurrentUser.AccountLoginTime = DateTime.Now; Here you remember to pass the Logininfo instance into the next interface, or the next interface will not get the current login information Administrator parent Interface Adminmain = new Administrator Parent interface (LoGininfo.currentuser); This.                        Hide ();                    Adminmain.show (); } else {MessageBox.Show ("username or password is wrong!                        "," prompt ");                        Textboxusername.text = "";                        Textboxpassword.text = "";                    Textboxusername.focus (); } reader.                Close (); } catch (SqlException ex) {MessageBox.Show ("DMS has an error:" + ex.)                Message); } finally {Conn.                Close (); }} else MessageBox.Show ("User name or password is blank, please reenter!")        "," prompt ");                 }        }

　　

C # WinForm Implementation remembers login status for user login