Delphi 3 Pro
Ready to Start Work with Delphi 3? We've included all the Delphi Hands On tutorials
from the last year on this CD to help you along - you'll find them here.
If you're an old Delphi guru, here are a few guidelines on version 3...
When installing Delphi 3 from the SuperCD, click the Delphi 3 Standard icon
in the Setup Launcher dialog. A set of dialogs now guides you through the remainder
of the installation process. Be sure to read the text in the 'Install Information'
panel before completing the installation.
If you already have a copy of Delphi 2 installed, you may want to uninstall
this prior to installing Delphi 3. If you do this, be sure you back up your
own program code first. Alternatively, you can install Delphi 3 into a new directory
and leave your existing installation of Delphi 2 alone. Note, however, if you
uninstall Delphi 2, this may have the effect of uninstalling certain files that
are required by Delphi 3. If you experience any problems, you should re-install
Delphi 3.
Once Delphi 3 has been installed, you will no doubt want to get down to some
programming. Anyone who is already familiar with an earlier release will find
no problem in adjusting to Delphi 3. For a quick tour of the new features, read
our introductory tutorial in the SuperCD pages of this month's PC Plus, then
refer to the 'What's New' section of the help system.
If you haven't used Delphi before, follow these instructions to create your
first application - a simple VAT calculator.
- Select File Menu, New Application.
- In the Standard palette at the top of the screen, click Edit (4th icon).
Click the form to add an Edit field to the Form. Repeat this procedure. Your
form should now contain two edit fields.
- Again, using the Standard palette, add two labels (3rd icon) and one button
(6th icon). Position these and resize the form so that it looks like this:
- Select Edit1 on the form. In the Object Inspector panel at
the left, select the Text property and delete the highlighted text, 'Edit1'.
Do the same to delete the text from Edit2.
5. Select Label1. In the Object Inspector, edit its Caption property to: 'Sub
Total:'. Select Label2 and edit its caption to 'Grand Total:'. Edit Button1's
Caption to 'Calculate'.
- On the form, double-click Button1. This will place you in the code editor.
Edit the procedure named TForm1.Button1Click by adding code as follows:
procedure TForm1.Button1Click(Sender: TObject);
var
subtot, vat: double;
errcode : integer;
begin
Val(Edit1.Text, subtot, errcode );
if errcode <> 0 then
ShowMessage('You must enter a number!')
else
begin
vat := subtot * 0.175;
Caption := 'VAT = ú' + FloatToStr(vat);
Edit2.Text := 'ú'+ FloatToStr(subtot + vat);
end;
end;
Run the application by pressing [F9]. Enter a value into the Subtotal field
and click the button. Try entering 100. You should see this:
Now enter the word, 'Ten'. This time, you should see this:
To understand what's going on in the code, you need to know the
following: In Delphi, each variable such as subtot is predeclared in the VAR
section. The Val() procedure converts a string to a number and returns an error
code if the conversion fails. ShowMessage() is a built-in procedure that displays
a simple message dialog. Caption refers to the Caption property of the current
Form and FloatToStr() is a function for converting a floating point value to
a string representation. If you need more detailed information, you can highlight
a procedure name in the editor and press [F1].
Product Details
Contact: Borland UK
Phone: +44 (0)118 932 0022
Fax: +44 (0)118 932 0017
Web: http://www.borland.com/
Email: desk@borlandinfo.co.uk
Online support: http://www.borland.com/devsupport/
(Note: no Borland support is available with this version).
Price: £469
Limitations: Personal use only. For full details, please
see the License
Agreement.
Minumum System Requirements: Intel 486DX/66 MHz or higher,
Windows 95 or Windows NT4 (SP2 or higher), 12Mb RAM (16MB recommended), 60Mb
hard disk space, VGA or higher resolution monitor. Networks supported: Windows
95 or NT 4.0 or higher.
Uninstall: Yes - Add/Remove Programs in the Control Panel.
Installation
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Click the icon to
the left to install Delphi 3. |