Ado. NET Delete and modify

Class

SqlConnection Conn;
SqlCommand cmd;

Public Usersdata ()
{
conn = new SqlConnection ("server=.; database=data0504;user=sa;pwd=123; ");
CMD = conn. CreateCommand ();
}

Public list<users> SelectAll ()
{
list<users> ulist = new list<users> ();
Cmd.commandtext = "Select *from Users";
Conn. Open ();
SqlDataReader dr = cmd. ExecuteReader ();
while (Dr. Read ())
{
Users u = new users ();
U.ids = dr["Ids"]. ToString ();
U.ucode = dr["Ucode"]. ToString ();
U.username = dr["UserName"]. ToString ();
U.password = dr["PassWord"]. ToString ();
U.nickname = dr["nickname"]. ToString ();
U.sex = Convert.toboolean (dr["Sex"]);
U.birthday = Convert.todatetime (dr["Birthday"]);
U.nation = dr["Nation"]. ToString ();

Ulist. ADD (U);
}
Conn. Close ();
return ulist;
}

public bool SelectAll (string UC)
{
BOOL has = false;

Cmd.commandtext = "Select *from Users where Ucode = @a";
Cmd. Parameters.clear ();
Cmd. Parameters.addwithvalue ("@a", UC);
Conn. Open ();
SqlDataReader dr = cmd. ExecuteReader ();
if (Dr. HasRows)
{
has = true;
}
Conn. Close ();
return has;
}

public bool UpdateUser (Users u)
{
bool OK = false;

Cmd. CommandText = "Update Users set PassWord = @a, [email protected],[email protected], [email protected] where Ucode = @d";
Cmd. Parameters.clear ();
Cmd. Parameters.addwithvalue ("@a", U.password);
Cmd. Parameters.addwithvalue ("@b", u.nickname);
Cmd. Parameters.addwithvalue ("@c", u.sex);
Cmd. Parameters.addwithvalue ("@d", U.ucode);
Cmd. Parameters.addwithvalue ("@e", u.birthday);
Conn. Open ();

int count = cmd. ExecuteNonQuery ();
if (Count > 0)
{
OK = true;
}

Conn. Close ();
return OK;
}

Public list<users> Insert1 () {
list<users> list = new list<users> ();
Users a= new users ();
Conn. Open ();
Cmd.commandtext = "INSERT into Users values (@a,@b,@c,@d,@e,@f,@g)";
Cmd. Parameters.clear ();
Cmd. Parameters.addwithvalue ("@a", A.ucode);
Cmd. Parameters.addwithvalue ("@b", a.username);
Cmd. Parameters.addwithvalue ("@c", A.password);
Cmd. Parameters.addwithvalue ("@d", a.nickname);
Cmd. Parameters.addwithvalue ("@e", a.sex);
Cmd. Parameters.addwithvalue ("@f", a.birthday);
Cmd. Parameters.addwithvalue ("@g", a.nation);
List. Add (a);

int count = cmd. ExecuteNonQuery ();
Conn. Close ();

if (Count > 0)
{
Console.WriteLine ("Add Success");

}
Else
{
Console.WriteLine ("Failure! ");
}

return list;

}

Console.backgroundcolor = Consolecolor.white;
Console.foregroundcolor = Consolecolor.black;
while (true)
{
Console.clear ();
New Test1 (). Datalook ();

while (true)
{
Console.WriteLine ();
Console.WriteLine ();
Console.Write ("Please enter the action you want to perform (add: 1, modify: 2, Delete: 3):");
string u = Console.ReadLine ();

if (U = = "1")
{
Users UUU = new users ();
UuU. Ucode = new Usersdata (). Newucode ();
Console.WriteLine ("Numbered:" + UUU. Ucode);
while (true)
{
Console.Write ("Please enter user name:");
UuU. UserName = Console.ReadLine ();
if (UUU. Username.trim (). Length > 0) {break;}
else {Console.WriteLine ("User name does not meet the rules!") "); }
}

while (true)
{
Console.Write ("Please enter password:");
UuU. PassWord = Console.ReadLine ();
Console.Write ("Please enter the new password again:");
String PassWord2 = Console.ReadLine ();

if (UUU. Password.trim (). Length > 4 && UUU. PassWord = = PassWord2)
{

Break
}
Else
{Console.WriteLine ("Password does not meet the rules!") ");
}
}

while (true)
{
Console.Write ("Please enter a nickname:");
UuU. Nickname = Console.ReadLine ();
if (UUU. Nickname.trim (). Length > 0) {break;}
else {Console.WriteLine ("Nickname does not meet the rules!") "); }
}

while (true)
{
Console.Write ("Please enter gender (male/female):");
String ssex = Console.ReadLine ();
if (ssex! = "Male" && ssex! = "female")
{
Console.WriteLine ("Gender input is wrong!") ");
}
Else
{
UuU. Sex = Ssex = = "Male"? True:false;
Break
}
}

while (true)
{
Console.Write ("Please enter your Birthday (2000-1-1):");
string bir = Console.ReadLine ();
Try
{
UuU. Birthday = Convert.todatetime (BIR);
Break
}
Catch
{
Console.WriteLine ("Date input Error! ");
}
}

while (true)
{
Console.Write ("Please enter your nationality (e.g. Han/Tibetan):");
string nat = Console.ReadLine ();
String snn = new Usernationdata (). Selectnationcode (NAT);
if (SNN = = "NULL")
{
Console.WriteLine ("Look no this nation!") ");
}
Else
{
UuU. Nation = SNN;
Break
}
}

Usersdata Udd = new Usersdata ();
bool OK = Udd. Insertuser (UUU);
if (OK)
{
Console.WriteLine ("added successfully! ");
}
Else
{
Console.WriteLine ("Add failed! ");
}

Console.readkey ();
Break
}

Modify

else if (U = = "2")
{
Console.Write ("Please enter the user number to be modified:");
String III = Console.ReadLine ();
BOOL h = new Usersdata (). SelectAll (iii);

if (h)
{
Users up = new users ();
Up. Ucode = III;

#region Change Password
Console.WriteLine ("This user information has been queried, can be modified");
while (true)
{
Console.Write ("Please enter a new password:");
String pwd1 = Console.ReadLine ();
Console.Write ("Please enter the new password again:");
String pwd2 = Console.ReadLine ();
if (pwd1 = = pwd2)
{
Up. PassWord = PWD1;
Break
}
Else
{
Console.WriteLine ("Two times password inconsistent!") Please re-enter! ");
}
}
#endregion

#region Modifying nicknames
while (true)
{
Console.Write ("Please enter a new nickname:");
String nn = Console.ReadLine ();
if (NN. Trim (). Length <= 0)
{
Console.WriteLine ("Input nickname does not meet the rules!") Please re-enter! ");
}
Else
{
Up. nickname = nn;
Break
}
}
#endregion

while (true)
{
Console.Write ("Please enter a new gender (male/female):");
string ss = Console.ReadLine ();
if (ss! = "Male" && ss! = "female")
{
Console.WriteLine ("Input Error! ");
}
Else
{
Up. Sex = SS = = "Male"? True:false;
Break
}
}
while (true) {
Try
{
Console.Write ("Please enter a new birthday:");
datetime birthday = new DateTime ();
Birthday = Convert.todatetime (Console.ReadLine ());
Up. Birthday = Birthday;
Break
}
catch {

Console.Write ("Please enter the correct date format:");
}

}
while (true)
{
Console.Write ("Please enter your nationality (e.g. Han/Tibetan):");
string nat = Console.ReadLine ();
String snn = new Usernationdata (). Selectnationcode (NAT);
if (SNN = = "NULL")
{
Console.WriteLine ("Look no this nation!") ");
}
Else
{
Up. Nation = SNN;
Break
}
}

BOOL B = new Usersdata (). UpdateUser (UP);
if (b)
{
Console.WriteLine ("Modified successfully! ");
}
Else
{
Console.WriteLine ("Modification failed!! ");
}

}
Else
{
Console.WriteLine ("Without this data");
}

Console.readkey ();
Break
}

Ado. NET Delete and modify