Computer Programming Concepts and Visual Basic David I. Schneider

402 Computer Programming Concepts and Visual Basic
COMMENTS
1. You can obtain extensive information about HTML and VBScript from the Help
menu in the ActiveX Control Pad. (If the documentation for VBScript is not
present on your computer, you can either download the documentation or read
it online at http://microsoft.com/scripting.)
2. HTML tags are not case sensitive. For instance, has the same effect as .
3. A TITLE element must placed inside the HEAD portion of an HTML document.
4. VBScript programs can contain code that is not in any procedure. If so, this
code is executed by Internet Explorer as soon as the Web page is displayed. It
is analogous to Visual Basic code found in the Form_Load event procedure.
5. Some features of Visual Basic that are not available in VBScript are ranges of
values and the Is keyword in Case clauses, Str and Val functions, the Open
statement, On Error GoTo statement, arrays declared with lower bound ≠ 0, line
labels, collections, and picture box controls.
6. If i is the index of a For...Next loop, in Visual Basic the final statement should
be Next i. In VBScript, the i must be dropped from the final statement.
7. To download the ActiveX Control Pad, enter the address
http://www.microsoft.com/gallery/tools/contents.htm into your browser and
follow the directions.
8. You can place your own custom-built ActiveX controls into an HTML document
provided the control has been compiled into an ocx file. However, in order
to use these controls you will have to ease Internet Explorer's safety level. To
invoke the lowest level of security, select Internet Options from Internet Explorer's
View menu, click on the Security tab, and select Low. Note: Before you
actually connect to the internet, reset the safety level to High.
9. Visual Basic allows you to place controls exactly where you want on a form.
The ActiveX Control Pad has a device, called an HTML Layout, that lets you
achieve the same result. An HTML Layout is actually an ActiveX control that
acts as a container for other controls. It has a grid like a form that allow for precision
alignment. The steps for creating an HTML Layout are as follows.
(a) From the ActiveX Control Pad, click on New HTML Layout in the File
menu. (A form-like window and a square toolbar containing about a dozen
icons will appear.)
(b) Place a control on the Layout with the click and drag method. To set the
properties of a control in the Layout, double-click on the control to produce
a Properties window.
(c) After all the controls have been drawn and their properties set, save the
Layout (in an ALX file).
(d) To insert the Layout into an HTML document, position the cursor at the
insertion point, and click on Insert HTML Layout in the Edit menu to open
a file-selection dialog box. Select the location and name of the file, and
then press the Open button. (An OBJECT element will be created for the
Layout.)
(e) Whenever you want to alter the Layout, place the cursor anywhere inside
the OBJECT element and select Edit HTML Layout from the Edit menu.