How to filter memo field in TDBF
lazarus / 16-Databases

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rocka1 · 2011-07-29 13:41

How to filter memo field in TDBF
I have a dbf file with 1 memo field, and 3 more string fields.

How to filter the memofield ?
Using TDbf

Right now I'm testing with:

Code: [Select]procedure TForm1.Button3Click(Sender: TObject);
var
  Myvar:String;
begin


Myvar:=(UPPERCASE('*'+(Edit1.Text)+'*'));//I have to use UPPERCASE to
catch the strings in edit1 inside words in the table


 Dbf1.Filter :='UPPERCASE(Field1) ='+quotedstr(Myvar)+' or
UPPERCASE(Field2) ='+quotedstr(Myvar)+' or
UPPERCASE(Field3)='+quotedstr(Myvar);  //+' or UPPERCASE(FieldMemo)
='+Quotedstr(Myvar);

 Dbf1.Filtered := true;                            
End;

How can add the memo field to filter ?

Ah, with the code above sometimes i get this error :


Exception Class 'External: SIGSEGV'
and open unit win32proc and highlight :
Result := UTF16ToUTF8(WideBuffer); 

Tnx

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garydale · 2011-07-29 14:44

I don't know if this will fix things, but you're trying too hard in
preparing your filter. Since you say it only happens sometimes, try
using a simpler filter to isolate the exact condition that causes the
failure.

Since you suspect it is the memo field, remove the string fields and
try to trigger the fault. If that doesn't work, try each of the string
fields.

Also, have you considered whether it may be a too-long filter
condition?

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rocka1 · 2011-07-29 19:21

In my tests Memo field are disabled in the filter, because I dont know
how to do it. Thats why my post.

About the error, I think that can be because I use western latin
strings in my table...
I've tested with the example of Lazarus, address_book, and theres no
errors. 

This is a little app that I want to move to Windows Mobile, a delphi
app export the table,
about 200-300 records, and I have few choices to export to, "CSV",
"DBF", "XLS""DB", "XML",
are some examples, and that file must be encrypted.

I'm thinking to use DCPciphers, in Delphi and then in Lazarus, since
the information
is about passwords that we/I have stored in that file.

The table here is only to read, not to change, i try to do it with
TSQLQuery, but I dont know how to connect it with the dbf file.

CDBF Explorer (based  on TDbf Component) can filter the memo, but how
does it works ?

Thanks