Return no records if FIndKey results in False?

Posted by jwilfong on Stack Overflow See other posts from Stack Overflow or by jwilfong
Published on 2010-03-28T07:50:40Z Indexed on 2010/03/28 7:53 UTC
Read the original article Hit count: 187

Filed under:

delphi

|

tdataset

Using TDataSet.FindKey you can locate records. When it results in True the datasets cursor will be positioned on the found record. When it results in False the cursor is not moved. This results in the record data prior to FindKey being issued being displayed in data aware components.

How can I code the result of FindKey to return an empty record?

    if Not tblSomeTable.FindKey([SomeSearchData]) then
    begin
        < code to return empty or move data cursor to neutral position >
    end;

Thanks, John

© Stack Overflow or respective owner

Related posts about delphi

TVirtualStringTree compatibility between Delphi 7 and Delphi 2010 - 'Parameter lists differ'

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I've made a form containing a TVirtualStringTree that works in Delphi 7 and Delphi 2010. I notice that as I move between the two platforms I get the message '...parameter list differ..' on the tree events and that the string type is changing bewteen TWideString (D7) and string (D2010). The only… >>> More
Convert Delphi 7 code to work with Delphi 2009

as seen on Stack Overflow - Search for 'Stack Overflow'
I have a String that I needed access to the first character of, so I used stringname[1]. With the unicode support this no longer works. I get an error: [DCC Error] sndkey32.pas(420): E2010 Incompatible types: 'Char' and 'AnsiChar' Example code: //vkKeyScan from the windows unit var KeyString:… >>> More
Book recommendation for moving from Delphi 6 to Delphi 2010

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I am a long time Delphi 6 developer. Looking for a book on Delphi 2010. Not only on the new features available in Delphi 2010, but more importantly, guideline on how different it is to develop applications in Delphi 2010, the architecture, standard and convention, etc. Thanks a lot. >>> More
Compile Delphi component package (bpl) for different Delphi versions

as seen on Stack Overflow - Search for 'Stack Overflow'
Hello. The situation is the following. Typically I use RAD Studio 2010 for Delphi development. I have some components I would like to redistribute in binary form (*.bpl without source). But I would like people to be able to use them despite of their Delphi version. But, for example, dcu files can… >>> More
Delphi Speech recognition delphi

as seen on Stack Overflow - Search for 'Stack Overflow'
I need create a programatic equivalent using delphi language... or could someone post a link on how to do grammars in peech recogniton using the delphi. sorry for my english... XML Grammar Sample(s): <GRAMMAR>  <RULE NAME="HelloWorld"… >>> More

Related posts about tdataset

Database application using MVC paradigm

as seen on Stack Overflow - Search for 'Stack Overflow'
In classic Delphi database application we have a form, a set of data-aware visual controls connected to TDataSets via TDataSources. If one wants to design database application using MVC model, where to place TDataSet components? Should they stay on form and therefore be a part of View? Or should they… >>> More
Return no records if FIndKey results in False?

as seen on Stack Overflow - Search for 'Stack Overflow'
Using TDataSet.FindKey you can locate records. When it results in True the datasets cursor will be positioned on the found record. When it results in False the cursor is not moved. This results in the record data prior to FindKey being issued being displayed in data aware components. How can I code… >>> More
Improve speed of own debug visualizer for Delphi 2010

as seen on Stack Overflow - Search for 'Stack Overflow'
I wrote Delphi debug visualizer for TDataSet to display values of current row, source + screenshot: http://delphi.netcode.cz/text/tdataset-debug-visualizer.aspx . Working good, but very slow. I did some optimalization (how to get fieldnames) but still for only 20 fields takes 10 seconds to show -… >>> More
Adding a calculated field to a Query at run time.

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm getting data using a query in Delphi, and would like to add a calculated field to the query before it runs. The calculated field is using values in code as well as the query so I can't just calculate it in SQL. I know I can attach an OnCalcFields Event to actually make the calculation, but the… >>> More
Do I have to allocate and free records when using TList<T> in Delphi?

as seen on Stack Overflow - Search for 'Stack Overflow'
The question more or less says it all. Given the following record structure: type TPerson = record Name: string; Age: Integer; end; PPerson = ^TPerson; TPersonList = TList<TPerson>; Is the following code valid? procedure ReadPeople(DataSet: TDataSet; PersonList:… >>> More