Example Delphi
Delphi Examples Collection
Today, Delphi is one of the popular desktop programming tool. There are thousand even million programmer in this world using delphi as their favorit tool. This site try to collect the examples, tips and tricks of Delphi programming. We collect, test them and redistribute the collection of delphi programming for you.
The following code does this better. You can select a value and display column. Also a method to free the memory allocated for the value objects.
Code by Steve Faleiro steve_goa@yahoo.com.
procedure disposeComboBoxObjects(c: TComboBox);
var
i: integer;
begin
if c.Items.Count > 0 then
for i := 0 to c.Items.Count - 1 do
Dispose(PVariant(c.Items.Objects[i]));
end;
// —- Populate a Combobox ———————————————
// —- for accessing the value, use:
// var
// s : PVariant;
// begin
// s := PVariant( lstServers.Items.Objects[lstServers.ItemIndex] );
// my_key := integer( s ^ ); // 0 then
c.ItemIndex := 0;
end;
Once again:
procedure disposeComboBoxObjects(c: TComboBox);
var
i: integer;
begin
if c.Items.Count > 0 then
for i := 0 to c.Items.Count - 1 do
Dispose(PVariant(c.Items.Objects[i]));
end;
// —- Populate a Combobox ———————————————
// —- for accessing the value, use:
// var
// s : PVariant;
// begin
// s := PVariant( lstServers.Items.Objects[lstServers.ItemIndex] );
// my_key := integer( s ^ ); // 0 then
c.ItemIndex := 0;
end;
(moderator please delete first two posts of mine.)
The following code does this better. You can select a value and display column. Also a method to free the memory allocated for the value objects.
Code by Steve Faleiro steve_goa@yahoo.com.
procedure disposeComboBoxObjects(c: TComboBox);
var
i: integer;
begin
if c.Items.Count > 0 then
for i := 0 to c.Items.Count - 1 do
Dispose(PVariant(c.Items.Objects[i]));
end;
// —- Populate a Combobox ———————————————
// —- for accessing the value, use:
// var
// s : PVariant;
// begin
// s := PVariant( lstServers.Items.Objects[lstServers.ItemIndex] );
// my_key := integer( s ^ ); // cast to your type
// ———————————————————————
procedure populateComboBox(c: TComboBox; ds: TDataSet;
KeyColumnIndex, DisplayColumnIndex: integer);
var
v: variant;
pt: PVariant;
begin
disposeComboBoxObjects(c);
c.Items.Clear;
with ds do begin
First;
while not EOF do begin
v := Fields[KeyColumnIndex].Value;
New(pt);
pt ^ := v;
c.Items.AddObject(Fields[DisplayColumnIndex].AsString, TObject(pt));
Next;
end;
end;
if c.Items.Count > 0 then
c.ItemIndex := 0;
end;