|
 Forum
Grundkurs
»Introduktion
»Snabbguide
»Komponenter
»Händelser
»Strängar
»Räkna med Delphi »Egna
typer
»Selektion
»Iteration
»Menyer
»Funktioner
»Arraystrukturer
Tips & Tricks
»Nya tips
»Blandat
»Databaser
»Filer
»Forms
»Grafik
»Internet
»Komponenter
»Matematik
»Multimedia
»Objekt/ActiveX
»Skrivare
»Strängar
»System
»Mest lästa tips
Artiklar
»Delphi och ADO
»Bygga en DLL
»Skapa en enkel rapport
»Hantera registret
»Enheter, units
»Klassen TCanvas
»Använd LookUp Controls
 Nya
tips
 Lägg
till tips
 Delphilänkar
 Gästbok
|
|
|
|
|
|
Databasoberoende
|
Kategori: Databaser
Inlagt: 2005-07-28
Läst: 1645
Inlagt av: Staffan Berg
|
|
Beskrivning |
|
Dessa databaskopplingar är så nära oberoende av databas du kan komma. Exemplena körs genom ADO-teknik och fungerar med kopplingar mot DBase, Access och Paradox.
|
|
Kod |
procedure RunSQL(sSQL : String);
var
qrySQL : TADOQuery;
begin
qrySQL := TADOQuery.Create(Application);
qrySQL.Connection := adoConnection;
qrySQL.SQL.Clear;
qrySQL.SQL.Text := sSQL;
qrySQL.ExecSQL;
qrySQL.Free;
end;
*******************************************************************************
procedure GetRecords(var qryField : TADOQuery; sSQL : String; LockType : TADOLockType = ltReadOnly);
begin
if qryField = Nil then begin
qryField := TADOQuery.Create(Application);
qryField.CursorType := ctOpenForwardOnly;
qryField.Connection := adoConnection;
end;
qryField.Close;
qryField.LockType := LockType;
qryField.SQL.Clear;
qryField.SQL.Add(sSQL);
qryField.Open;
end;
*******************************************************************************
Example of use for RunSQL:
...............................................................................
var
sSQL : String;
begin
sSQL := 'insert into TB_Log (UserId,UserName) values ("My User Id","My User Name")';
RunSQL(sSQL);
...............................................................................
Example of use for GetRecords:
...............................................................................
var
qrySetup : TADOQuery;
begin
GetRecords(qrySetup,'select * from TB_Setup',ltOptimistic);
if qrySetup['IsRegistered'] then begin
ShowMessage('Your are a Registered user')
else
ShowMessage('Your are NOT a Registered user');
//DO NOT forget to free it when done.
qrySetup .Free;
...............................................................................
Another example for the use for GetRecords:
...............................................................................
var
qryUsers : TADOQuery;
begin
GetRecords(qryUsers,'select * from TB_Users',ltOptimistic);
while NOT qryUsers.Eof do begin
if qryUsers['UserName'] = 'Abdulaziz' then
ShowMessage('It's me!!!');
qryUsers.Next;
end;
qryUsers.Free;
|
|
|