Filtering data on DBGrid on dbedit keypress
Question
I programming with adodb/dbgo and try to use this code:
procedure TfrMain.dbeNoMejaKeyPress(Sender: TObject; var Key: Char);
begin
dmWarbam.TblTrans_temp.Filtered := False;
dmWarbam.TblTrans_temp.Filter := 'ID_ITEM = ' + QuotedStr(dbeNoMeja.Text);
dmWarbam.TblTrans_temp.Filtered := True;
end;
and
procedure TfrMain.dbeNoMejaChange(Sender: TObject);
begin
dmWarbam.TblTrans_temp.Filtered := False;
dmWarbam.TblTrans_temp.Filter := 'ID_ITEM = ' + QuotedStr(dbeNoMeja.Text);
dmWarbam.TblTrans_temp.Filtered := True;
end;
But none of above can work, when i press key on dbeNoMeja it didn't filter but instead the dataset inserting broken/incomplete data to database.
Can someone give me some example that working (full code)
Solution
If the dbedit is connected to the same table as the one you want to filter you have a problem, because the table goes into the dsEdit state once you start entering text.
Use a normal TEdit, and append a wildcard (*) to the string in the filter
dmWarbam.TblTrans_temp.Filter := 'ID_ITEM = ' + QuotedStr(edtNoMeja.Text+'*');
OTHER TIPS
Code example adapted from Delphi-Neftalí. Nice and simple!
procedure TForm1.Edit1Change(Sender: TObject);
begin
// incremental search
ClientDataSet1.Locate('FirstName', Edit1.Text, [loCaseInsensitive, loPartialKey]);
Exit;
// actual data filtering
if (Edit1.Text = '') then begin
ClientDataSet1.Filtered := False;
ClientDataSet1.Filter := '';
end
else begin
ClientDataSet1.Filter := 'FirstName >= ' + QuotedStr(Edit1.Text);
ClientDataSet1.Filtered := True;
end;
end;
Setting ClientDataSet's provider to ADO DB (in your case):
Path := ExtractFilePath(Application.ExeName) + 'Data.MDB';
// Exist the MDB?
if FileExists(path) then begin
ClientDataSet1.ProviderName := 'DSProvider';
ADOQ.Open;
ClientDataSet1.Active := True;
ADOQ.Close;
ClientDataSet1.ProviderName := '';
lbldata.Caption := ExtractFileName(path);
Exit;
end;
I found a good solution in Expert Exchange,
unit dbg_filter_u;
interface
uses
Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
Grids, DBGrids, DBTables, Db, StdCtrls;
type
TForm1 = class(TForm)
Table1: TTable;
DataSource1: TDataSource;
Query1: TQuery;
DBGrid1: TDBGrid;
cbFilterBox: TComboBox; //a hidden combobox (Style = csDropDownList)
procedure Table1AfterOpen(DataSet: TDataSet);
procedure Table1AfterPost(DataSet: TDataSet);
procedure DBGrid1TitleClick(Column: TColumn);
procedure cbFilterBoxChange(Sender: TObject);
procedure cbFilterBoxClick(Sender: TObject);
procedure cbFilterBoxExit(Sender: TObject);
private
Procedure FillPickLists(ADBGrid : TDBGrid);
public
{ Public declarations }
end;
var
Form1: TForm1;
implementation
{$R *.DFM}
//For Accessing some Protected Methods
type TCDBGrid = class(TCustomDBGrid);
//Storing the Values into the Picklist-Propertys of the asscociated Columns,
//this may cost time depending on the amount of the dataset
Procedure TForm1.FillPickLists(ADBGrid : TDBGrid);
const
SQL_Text = 'Select Distinct %s From %s';
var
q : TQuery;
i : integer;
Begin
If (Assigned(ADBGrid)) and
(Assigned(ADBGrid.Datasource)) and
(Assigned(ADBGrid.Datasource.DataSet)) Then
Begin
If (ADBGrid.Datasource.DataSet is ttable) Then
begin
q := TQuery.Create(self);
try
try
q.DatabaseName := TTable(ADBGrid.Datasource.DataSet).DataBaseName;
for i := 0 to ADBGrid.Columns.Count - 1 do //for each column
begin
if ADBGrid.Columns[i].Field.FieldKind = fkData then //only physical fields
begin
ADBGrid.Columns[i].ButtonStyle := cbsNone; //avoid button-showing
ADBGrid.Columns[i].PickList.Clear;
q.Close;
q.SQL.text := Format(SQL_Text,[ADBGrid.Columns[i].Field.FieldName,TTable(ADBGrid.Datasource.DataSet).TableName]);
q.Open;
While not q.eof do
begin
ADBGrid.Columns[i].PickList.Add(q.Fields[0].AsString);
q.next;
end;
q.close;
end;
end;
finally
q.free;
end;
except
raise;
end;
end else
Raise exception.Create('This Version works only for TTables');
end else
Raise Exception.Create('Grid not properly Assigned');
end;
//Initial-Fill
procedure TForm1.Table1AfterOpen(DataSet: TDataSet);
begin
FillPickLists(DBGrid1);
end;
//Refill after a change
procedure TForm1.Table1AfterPost(DataSet: TDataSet);
begin
FillPickLists(DBGrid1);
end;
//Show a Dropdownbox for selecting, instead the title on Titleclick
procedure TForm1.DBGrid1TitleClick(Column: TColumn);
var
ARect : Trect;
DummyTC : TColumn;
begin
If column.PickList.Count > 0 then
begin
cbFilterbox.Items.Assign(column.PickList);
ARect := TCDBGrid(Column.Grid).CalcTitleRect(Column,0,DummyTC);
cbfilterBox.top := Column.Grid.Top+1;
cbfilterBox.left := Column.Grid.left+Arect.Left+1;
cbFilterbox.Width := Column.Width;
cbFilterBox.Tag := Integer(Column); //Store the columnPointer
cbFilterBox.Show;
cbFilterBox.BringToFront;
cbFilterBox.DroppedDown := True;
end;
end;
//Build up the Filter
procedure TForm1.cbFilterBoxChange(Sender: TObject);
begin
cbFilterBox.Hide;
if cbFilterBox.Text <> TColumn(cbFilterBox.Tag).Title.Caption then
begin
Case TColumn(cbFilterBox.Tag).Field.DataType of
//Some Fieldtypes
ftstring :
TTable(TDBGrid(TColumn(cbFilterBox.Tag).Grid).Datasource.Dataset).Filter :=
TColumn(cbFilterBox.Tag).Field.FieldName+' = '+QuotedStr(cbFilterBox.Text);
ftInteger,
ftFloat :
TTable(TDBGrid(TColumn(cbFilterBox.Tag).Grid).Datasource.Dataset).Filter :=
TColumn(cbFilterBox.Tag).Field.FieldName+' = '+cbFilterBox.Text;
end;
TTable(TDBGrid(TColumn(cbFilterBox.Tag).Grid).Datasource.Dataset).Filtered := True;
end;
end;
//some Hiding-events
procedure TForm1.cbFilterBoxClick(Sender: TObject);
begin
cbFilterBox.Hide;
end;
procedure TForm1.cbFilterBoxExit(Sender: TObject);
begin
cbFilterBox.Hide;
end;
end.
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