asked on

Dbgrid Copy a cell to another cell - Problem.. Error

This is a piece of code
.......
If Key=13 then
Begin

Str1:=Copy(Edit1.Text,1,1);
Str2:=Copy(Edit1.Text,2,1);
Str3:=Copy(Edit1.Text,3,1);
Str4:=Copy(Edit1.Text,4,1);
Edit1.Visible:=False;
Dbgrid1.Visible:=True;

DataSource1.DataSet.FieldDefs.Clear;

PostToDBGridCell(DBGrid1, 1, 1,Str1); ///// Column ,Row , String
PostToDBGridCell(DBGrid1, 1, 2,Str2);
PostToDBGridCell(DBGrid1, 1, 3,Str3);
PostToDBGridCell(DBGrid1, 1, 4,Str4);

DBGrid1.Refresh;
End;
....
....
procedure TForm1.Button3Click(Sender: TObject);
begin

//--- Create Maximum
DataSource1.DataSet.First;

Str1:=DataSource1.DataSet.Fields.Fields[0].AsString; //Try to copy from cell 1st Column /1st Row
Str2:=DataSource1.DataSet.Fields.Fields[1].AsString; //Try to copy from cell 1st Column /2nd Row
Str3:=DataSource1.DataSet.Fields.Fields[2].AsString;
Str4:=DataSource1.DataSet.Fields.Fields[3].AsString;

Str5:=Str1+Str2+Str3+Str4;
PostToDBGridCell(DBGrid1, 2, 1,Str5); ////// 2 Column 1 Row
end;
................

The problem is that when i use PostToDBGridCell :

PostToDBGridCell(DBGrid1, 2, 1,Str5); ////// 2 Column 1 Row

PostToDBGridCell is a procedure that works fine when i try to copy text from Edit1.Text
to the cells in the 1 column.

Problem :
Only one character appear in the 1st cell, 1st Row of Column 2 (Character from Str4).

Maybe the problem is when i try to copy to Str(x) from the first four rows of column 1
I dont know.
The application is higly unstable... Sometimes reboot required...
I hope i was clear enough :/

Thanks in advance

CodedK

ASKER

I use descenting filter on the 1st column...

calinutz

Did you try to ShowMessage() with your resulting string (after the sum)?
HowAbout your Procedure postToDBGrid... does it allow a string ? Paste the procedure also if you want your problem solved. It maybe coming from the procedure...the error.

kretzschmar

not read the entire question complete

just to say forget cells and rows use fields and datarecord,
means you cannot address a "dbgrid-cell" with row and column

looking later again

meikl ;-)

CodedK

ASKER

How can i do that meikl?
I tried to do that with fields ..but not datarecords...
Dont have enough expirience with Database and all that...

But the problem is why PostToDBGridCell works for one cell and the next moment dont work for the other cell (Next Column..) ???

The procedure is :

procedure PostToDBGridCell(DBGrid: TDBGrid; Col, Row: Integer; S: string);
(*var FN:string;*)
begin
with DBGrid.DataSource.DataSet do
begin
if (State<>dsBrowse) then
Cancel;
if (RecordCount>=Row) then
begin
if (FieldCount>=Col) then
begin
First;
MoveBy(Row-1);
Edit;
Fields[Col-1].AsString := S;
Post;
end;
end;
end;
end;

Is there a way to temporary disable the filter (Descenting) of a Column and then filter it back ???

I think that this may cause the problems.

I tried with DataSource1.DataSet.Filtered:=False;
but gives a read-only error for table1 and then when i set the table1 to read-only=false
i get a memory error.......

Thanks

esoftbg

procedure CopyDBGridCellToCell(DBGrid: TDBGrid; ColSource, RowSource, ColTarget, RowTarget: Integer);
var
qry: TQuery;
S: string;
begin
with DBGrid.DataSource.DataSet do
begin
if (State<>dsBrowse) then
Cancel;
if ((RecordCount>=RowSource) and (RecordCount>=RowTarget)) then
begin
if ((FieldCount>=ColSource) and (FieldCount>=ColTarget)) then
begin
qry := TQuery.Create(nil);
try
qry.SQL.Text := 'SELECT * FROM SINGERS';
qry.Active := True;
qry.MoveBy(RowSource-1);
S := qry.Fields[ColSource-1].AsString;
DBGrid.DataSource.DataSet.First;
DBGrid.DataSource.DataSet.MoveBy(RowTarget-1);
DBGrid.DataSource.DataSet.Edit;
DBGrid.DataSource.DataSet.Fields[ColTarget-1].AsString := S;
DBGrid.DataSource.DataSet.Post;
finally
qry.Active := False;
qry.Destroy;
end;
end;
end;
end;
end;

procedure TForm1.Button1Click(Sender: TObject);
begin
CopyDBGridCellToCell(DBGrid, 2, 3, 2, 8);
end;

esoftbg

a little bit improved version:

procedure CopyDBGridCellToCell(DBGrid: TDBGrid; ColSource, RowSource, ColTarget, RowTarget: Integer; T: string);
var
qry: TQuery;
S: string;
begin
with DBGrid.DataSource.DataSet do
begin
if (State<>dsBrowse) then
Cancel;
if ((RecordCount>=RowSource) and (RecordCount>=RowTarget)) then
begin
if ((FieldCount>=ColSource) and (FieldCount>=ColTarget)) then
begin
qry := TQuery.Create(nil);
try
qry.SQL.Text := T;
qry.Active := True;
qry.MoveBy(RowSource-1);
S := qry.Fields[ColSource-1].AsString;
DBGrid.DataSource.DataSet.First;
DBGrid.DataSource.DataSet.MoveBy(RowTarget-1);
DBGrid.DataSource.DataSet.Edit;
DBGrid.DataSource.DataSet.Fields[ColTarget-1].AsString := S;
DBGrid.DataSource.DataSet.Post;
finally
qry.Active := False;
qry.Destroy;
end;
end;
end;
end;
end;

procedure TForm1.btnCopyCellToCellClick(Sender: TObject);
var
T: string;
begin
T := qryNames.SQL.Text;
CopyDBGridCellToCell(DBGrid, 2, 3, 2, 8, T);
end;

CodedK

ASKER

Thank you very much Esoftbg.
I should mention that the previous code i used is also from u. :)

But what is the problem with my code. I use PostToDBGrid for the 1st column and works but when i try to the next doesn't.. ?????

esoftbg

Hi CodedK,

> Maybe the problem is when i try to copy to Str(x) from the first four rows of column 1

Str1:=DataSource1.DataSet.Fields.Fields[0].AsString; //Try to copy from cell 1st Column /1st Row
Str2:=DataSource1.DataSet.Fields.Fields[1].AsString; //Try to copy from cell 1st Column /2nd Row
Str3:=DataSource1.DataSet.Fields.Fields[2].AsString;
Str4:=DataSource1.DataSet.Fields.Fields[3].AsString;

that is not Str(x) from the first four rows of column 1,
that is Str(x) from the first four columns of the current row of the DBGrid (Only the user knows which row is current)

esoftbg

DBGrid.DataSource.DataSet.First; // Sets DBGrid "First" Row to be current
DBGrid.DataSource.DataSet.MoveBy(RowTarget-1); // Moves DBGrid "RowTarget" Row to be current

Obviously I did not understand your question and made a wrong example .... Do you need a correct one ?

CodedK

ASKER

About your last comment Esoftbg...

DBGrid.DataSource.DataSet.First; // Sets DBGrid "First" Row to be current
DBGrid.DataSource.DataSet.MoveBy(RowTarget-1); // Moves DBGrid "RowTarget" Row to be current...

I tried this :

procedure TForm1.Button3Click(Sender: TObject);
begin

DBGrid1.DataSource.DataSet.First;
Str1:=DBGrid1.DataSource.DataSet.Fields.Fields[0].AsString;

//DBGrid1.DataSource1.DataSet.First;
DBGrid1.DataSource.DataSet.MoveBy(-1); // I also tried MoveBy(1)
Str2:=DBGrid1.DataSource.DataSet.Fields.Fields[1].AsString;

//DBGrid1.DataSource1.DataSet.First;
DBGrid1.DataSource.DataSet.MoveBy(-2);
Str3:=DBGrid1.DataSource.DataSet.Fields.Fields[2].AsString;

//DBGrid1.DataSource1.DataSet.First;
DBGrid1.DataSource.DataSet.MoveBy(-3);
Str4:=DBGrid1.DataSource.DataSet.Fields.Fields[3].AsString;

Str5:=Str1+Str2+Str3+Str4;
ShowMessage(Str5); // A random cell value appears...

PostToDBGridCell(DBGrid1, 2, 1,Str5);
end;
-----------------------------------------------------------------------------------------------
The result is the same as before when i had
DBGrid1.DataSource.DataSet.Fields.Fields[something].AsInteger;
Only one value was written in the next column (Random)...???

Things become very unpredictable.

Everytime i run the application different errors come up.
I had to close Delphi and restructure the table many times...
......
If u can write an example code...please :)
Thanks.

ASKER CERTIFIED SOLUTION

esoftbg

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esoftbg

begin
DBGrid1.DataSource.DataSet.First;

Str1:=DBGrid1.DataSource.DataSet.Fields.Fields[0].AsString;

DBGrid1.DataSource.DataSet.Next; // Next record is the Second one;
Str2:=DBGrid1.DataSource.DataSet.Fields.Fields[1].AsString;

DBGrid1.DataSource.DataSet.Next; // Next record is the Third one;
Str3:=DBGrid1.DataSource.DataSet.Fields.Fields[2].AsString;

DBGrid1.DataSource.DataSet.Next; // Next record is the Fourth one;
Str4:=DBGrid1.DataSource.DataSet.Fields.Fields[3].AsString;

Str5:=Str1+Str2+Str3+Str4;
ShowMessage(Str5); // A random cell value appears...

PostToDBGridCell(DBGrid1, 2, 1,Str5);
end;

esoftbg

Take a look at the Length(Str5) ....
It may be biggest than the size of the field into that will be copied;

esoftbg

download an example from:
page: http://www.geocities.com/esoftbg/
link: Q_21156333.zip

CodedK

ASKER

Thanks Esoftbg.

Found the problem.. :)

>> DBGrid1.DataSource.DataSet.Next; // Next record is the Third one;
Str3:=DBGrid1.DataSource.DataSet.Fields.Fields[2].AsString;

But the problem was in Fields[2].. I thought that [2] was 2 down from the first cell moving vertical.
But it was moving horizontal ...
So when i tried Fields[1] then [2] ... with next .. it was moving diagonal...!
--->Error (List out of bounds and memory access violations)

So.. what i was looking for was

DBGrid1.DataSource.DataSet.First;
Str1:=DBGrid1.DataSource.DataSet.Fields.Fields[0].AsString;

DBGrid1.DataSource.DataSet.Next;
Str2:=DBGrid1.DataSource.DataSet.Fields.Fields[0].AsString;

DBGrid1.DataSource.DataSet.Next;
Str3:=DBGrid1.DataSource.DataSet.Fields.Fields[0].AsString;

DBGrid1.DataSource.DataSet.Next;
Str4:=DBGrid1.DataSource.DataSet.Fields.Fields[0].AsString;

Str5:=Str1+Str2+Str3+Str4;
ShowMessage(Str5);

Thank you very much for you time :))
I will grand as accepted answer your procedure ... Cause it automates what i was looking for.
Though i dont understand much...

Question in your procedure you have TQuery and SQL mentioned....
I use a DBase table is there any problem with that?

Thank you again man :)

esoftbg

I use TQuery and SQL to access a Paradox table via BDE, so there is no problem to use TQuery and SQL to access DBase via BDE. If you access DBase via ADO you may use TADOQuery and SQL .... There is no problem ....

esoftbg

I am glad that you found and solve the problem !