Solved

testing for an empty dataset before deleting a record

Posted on 1998-09-30
1
1,261 Views
Last Modified: 2006-11-17
How can i test if the dataset is empty before allowing an button click event to delete a record?

If it is empty i want to respond with an appropriate dialog box, but i can't figure out an effective way to check first that it doesn't happen to be empty

any clues?
0
Comment
Question by:npepper
1 Comment
 

Accepted Solution

by:
dejohn99 earned 50 total points
ID: 1341295
Either of these should work.

Wherever I have used DataSet1.Delete, you should put your normal Delete processing, whatever it may be.

procedure btnDelete1Click (Sender: TComponent)
begin
    if DataSet1.RecordCount = 0 then
        raise Exception.Create ('Dataset '+DataSet1.Name+' is empty');

    DataSet1.Delete;
end;



procedure btnDelete2Click (Sender: TComponent)
begin
    if DataSet1.RecordCount = 0 then
        MessageDlg ('Dataset '+DataSet1.Name+' is empty',
            mtError, [ mbCancel ], 0);
    else
        DataSet1.Delete;
end;


If you are concerned that the RecordCount may not be kept current, you might try this:

procedure btnDelete3Click (Sender: TComponent)
begin
        { EOF and BOF will only both be true for an empty dataset }
        if DataSet1.EOF and DataSet1.BOF then
            MessageDlg ('Dataset '+DataSet1.Name+' is empty',
                mtError, [ mbCancel ], 0)
        else
            DataSet1.Delete;
end;


0

Featured Post

Gigs: Get Your Project Delivered by an Expert

Select from freelancers specializing in everything from database administration to programming, who have proven themselves as experts in their field. Hire the best, collaborate easily, pay securely and get projects done right.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
How to define IfThen functions in one common unit? 4 50
Create a path if not exists 7 77
How to build JSON File in Delphi 6 3 32
Firemonkey allowing RTL on android 6 30
Objective: - This article will help user in how to convert their numeric value become words. How to use 1. You can copy this code in your Unit as function 2. than you can perform your function by type this code The Code   (CODE) The Im…
Have you ever had your Delphi form/application just hanging while waiting for data to load? This is the article to read if you want to learn some things about adding threads for data loading in the background. First, I'll setup a general applica…
In a recent question (https://www.experts-exchange.com/questions/28997919/Pagination-in-Adobe-Acrobat.html) here at Experts Exchange, a member asked how to add page numbers to a PDF file using Adobe Acrobat XI Pro. This short video Micro Tutorial sh…
Microsoft Active Directory, the widely used IT infrastructure, is known for its high risk of credential theft. The best way to test your Active Directory’s vulnerabilities to pass-the-ticket, pass-the-hash, privilege escalation, and malware attacks …

776 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question