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unit dbform;
{$mode objfpc}{$H+}
interface
uses
SysUtils, db, sqldb, Forms, Controls, Dialogs, DBGrids, dbloginform,
mssqlconn; // mssqlconn was added to 2.6.1, you need a recent 2.6.1
type
{ TForm1 }
TForm1 = class(TForm)
Datasource1: TDatasource;
DBGrid1: TDBGrid;
MSSQLConnection1: TMSSQLConnection;
SQLQuery1: TSQLQuery;
SQLTransaction1: TSQLTransaction;
SybaseConnection1: TSybaseConnection;
procedure FormCreate(Sender: TObject);
private
public
end;
var
Form1: TForm1;
implementation
{$R *.lfm}
{ TForm1 }
procedure TForm1.FormCreate(Sender: TObject);
type
DBType=(MSSQL,SybaseASE);
var
ChosenDB: DBType;
Connection: TSQLConnection;
DBSelected: string;
GoodConnection: boolean;
LoginForm: dbloginform.TLoginForm;
Password: string;
UserCancel: boolean;
begin
// Let user login.
GoodConnection:=false;
UserCancel:=false;
LoginForm:=dbloginform.TLoginForm.Create(Nil);
try
while (GoodConnection=false) and (UserCancel=false) do
begin
if LoginForm.ShowModal=mrOK then
begin
DBSelected:=LoginForm.DatabaseType.Items[LoginForm.DatabaseType.ItemIndex];
// Use the text in the databasetype combobox to see what db the user wants.
// Then we point our Connection to the relevant TSQLConnection descendant.
case UpperCase(DBSelected) of
'MS SQL SERVER':
begin
ChosenDB:=MSSQL;
Connection:=MSSQLConnection1;
end;
'SYBASE ASE':
begin
ChosenDB:=SybaseASE;
Connection:=SybaseConnection1;
end
else
begin
showmessage('Unknown database type '+DBSelected+' chosen. Aborting. Pleae fix the code!');
Application.Terminate;
end;
end;
if LoginForm.OSAuthentication.Checked then
begin
// Use operating system credentials - mssqlconn
// expectes empty username/password then.
Connection.UserName:='';
Connection.Password:='';
end
else
begin
// Use regular username/password
Connection.UserName:=LoginForm.User.Text;
Connection.Password:=LoginForm.Password.Text;
end;
if LoginForm.Port.Text<>'' then
begin
Connection.HostName:=LoginForm.Server.Text+':'+LoginForm.Port.Text;
end
else
begin
// Default/no port. Let the connector sort it out.
Connection.HostName:=LoginForm.Server.Text;
end;
Connection.DatabaseName:=LoginForm.Database.Text;
// Actually, this should work both on MS SQL and Sybase server, so no need to change it:
//SQLQuery1.SQL.Text:='select * from sysservers';
// Everything set up, now connect to database.
// First make sure the other connection is switched off:
if ChosenDB=MSSQL then
begin
SybaseConnection1.Connected:=false;
end
else
begin
MSSQLConnection1.Connected:=false;
end;
SQLTransaction1.DataBase:=Connection;
SQLQuery1.DataBase:=Connection;
try
Connection.Connected:=true;
GoodConnection:=true;
except
on E: Exception do
begin
GoodConnection:=false;
showmessage('Error connecting to database. Technical details: '+E.ClassName+'/'+E.Message);
end;
end;
end
else
begin
showmessage('User cancelled login. Stopping.');
UserCancel:=true; //Tell the loop to release us.
Application.Terminate;
end;
end;
if UserCancel=false then
begin
// Now activate the components "downstream" of the database connection to get the data
// displayed to the user
try
SQLTransaction1.Active:=true;
SQLQuery1.Active:=true;
GoodConnection:=true;
except
on E: Exception do
begin
GoodConnection:=false;
showmessage('Error connecting to database. Technical details: '+E.ClassName+'/'+E.Message);
end;
end;
end;
finally
// Close the form and release memory
LoginForm.Release;
end;
end;
end.
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