Figure 1: Visual Speller 2.0

As with any custom control, the best part of using Spell Checker is the minimal amount of coding you have to do to get great functionality and features. By placing the control on the form and adding one or two dozen lines of code, you can check spelling of a block of text, see a list of suggested replacements for words the checker can't find in the dictionary, correct misspelled words, add words to a custom dictionary you specify, and more. In addition, users can customize a number of options with no coding on your part, including the relative amount of memory the control consumes, whether acronyms should be checked, which dictionary to use, and more.        You can even completely ignore all the built-in functionality the control provides if you want. Instead, you can customize the behavior of the control, such as disabling display of the standard "Word Not Found in Dictionary" dialog box, and roll your own functionality using the control's event and property procedures. Sample code for adding this control to a page is shown in Figure 2        My only problem with Visual Speller 2.0 as a Web-enabled package wasn't with the control but with the specifications and support provided with it. To programmatically customize the control's behavior, you work with a bunch of the control's properties. Unfortunately, the help file only showed the symbolic values for the properties. Because VBScript doesn't do constants, I was forced to spelunk my way through the sample apps provided with the demo download zip file to find a BAS file that would show the value of the constants described in the help. But hey, it was no big deal. MicroHelp MhIni Control        It seems as if MicroHelp makes more custom controls than anybody else. Rather than sell controls one at a time, the company hawks libraries of ActiveX controls, as well as older VBXs, that do everything but clean the coffee stains from your keyboard. These controls range from simple enhancements to standard controls, such as a 3D check box, to full-blown control implementations of otherwise impossible or tedious coding tasks, such as the mhCallBack control or the playing card control.

Figure 3: mhIni control from MicroHelp

A must-have for anyone's custom control toolbox is the mhIni control now available from MicroHelp. The mhIni control (see Figure 3), part of the company's OleTools collection, makes it a snap to set and retrieve data from either 16-bit INI files or the Windows® registry. If you've ever written a wrapper function around one or more of the ProfileString group of API functions or forgotten to initialize a string passed to the Windows API, you'll find welcome stability in this control. If you're setting or retrieving values in the registry, you can forget about the nuisance of getting a handle to the key you want to work with. Though it certainly raises security issues, the mhIni control gives a Web page access to the browsing workstation's registry easily and cleanly.        To work with either INI files or the registry, you set the Action property of the control to an appropriate numeric value for the task you want to perform, such as setting a registry key value or removing an INI file entry, assign its metadata value to the appropriate properties, such as the key and subkey you're interested in, and set a control's text or a variable against the property that will contain the value you want. In addition to its get and out functions (used to retrieve and set INI and registry values), the control also can help enumerate key values, comment/uncomment settings in INI files, and encrypt values (see Figure 4). Microsoft Calendar        These days, most applications make use of a third-party calendar control to help the user select a date, or use a home-grown control. Your Web pages as well can naturally shine with a cool looking calendar component rather than with a tired old edit control.

Figure 5: Microsoft Calendar component

A number of calendar controls are available from different developers, but the Microsoft® Calendar component (see Figure 5) is probably the best of the four I looked at. In addition, the control's extensive set of event, property, and method procedures make it flexible and adaptable to whatever application you implement it in.        Programming the Microsoft Calendar component is a snap. There are enough design-time-settable properties that you needn't write much code to implement the component. Come runtime, two methods, HideControl and ShowControl, make it easy to display the control when it is needed to select a date and to hide it when the control is no longer needed.        When a user has selected a date by double-clicking on the control or by pressing the Enter key, you can easily trap the date selected by evaluating the Value property. In addition, you can determine separately the year, month, and day of the date the user has selected with different properties, rather than having to parse the Value property. Another property will tell you the number of days in the month of the selected date. This saves you from a switch statement where you would have to evaluate the month selected, then return the number of days in the month (if only I remembered that darn rhyme).        Finally, a number of methods such as NextDay or PreviousMonth can help you change the context of the date control via code, something the user does by clicking on different buttons and combo boxes directly on the control. Figure 6 shows sample code to get this control on a page. DameWare ChkList        You'd probably agree that list boxes and checkboxes are not exactly the most exciting controls around, nor are they what the Microsoft moniker-makers had in mind when they came up with the term "active content." But combining these two control items into one control can get interesting.

Figure 7: ChkList component from DameWare

A few developers have made integrated checklist controls available, and the ChkList ActiveX component (see Figure 7) from DameWare Development is a pretty good implementation. Figure 8 shows a few examples of the ChkList control. Benefits of this control? Well, your users get a break from the tired multi-select list boxes, and the graphical elements of the control definitely gives your page an esthetic boost. ProtoView InterAct        Supposedly a picture can tell a thousand words. Of course, you're reading this article and not viewing my childhood stick figures. But if your Web-based app requires your users to model an idea or to illustrate a process, then ProtoView's InterAct ActiveX control (see Figure 9) is a must have.

Figure 9: InterAct control from ProtoView

The InterAct control uses a traditional interface to let a user draw, process, and model. The user places shapes, known as entities, selected from a toolbox on a work area, and then formats them with text and color. Next, the user draws lines between the entities describing their relationship. This functionality helps the user to model a process, such as publishing a magazine, creating an entity-relationship (ER) diagram, or whatever. If your user doesn't like the default appearance of different shapes, or dislikes the default relationship the tool creates between entities, no problem. These can be changed by working with the control's interface of classes and rules.        To implement this ActiveX component, add it to your Web development environment, then draw an InterAct work area on the HTML page. That's it! To use the component, your user right-clicks on the work area and makes the menu choice to display the InterAct toolbox. The toolbox includes all of the controls your user will need to create a diagram. The toolbox gives you quick access to zoom controls; cut, copy, and paste buttons; and all of the entity and relation drawing tools.        One of the best parts of this tool is that it doesn't lose any of its glitter used as a component as compared to the runtime application, which is also part of the downloadable package. Your user can save diagrams they create while using the component , as well as loading existing controls and editing them. The diagrams are saved in a proprietary format.        After you draw a work area for the control on an HTML page, a robust set of properties, events, and methods make it possible to customize the behavior of the component. For example, you can specify what occurs after the user has created an entity, drawn a relation, or saved a diagram, and you can define classes and rules for the component in advance. Another option is using data supplied by your user somewhere on the page to create a diagram completely programmatically.

Figure 11: Result of code in Figure 10

The code snippet in Figure 10 demonstrates how you can create entities and relations in code. Figure 11 shows the control after the code is run. The code first checks to see if a specific rule exists that draws a line between two rectangles. If the rule doesn't exist, it is created. Next, three entities are created in the diagram, and then relationship lines are drawn between each. This control certainly isn't Visio or ERwin, two of the top modeling/diagramming tools. But it's pretty nice for a downloadable control. Visual Components First Impression 2.0        Another useful control is First Impression 2.0 from Visual Components. First Impression is a first-class charting control that gives your browsing user the capability to build nifty charts directly on your Web site, based on data your app or your users supply. Your user can customize their chart using every bell and whistle known to charting (see Figure 12), or you can customize the chart directly from code. Simply stated, there is little you can do with Microsoft Chart that you cannot execute with this control.

Figure 12: First Impression 2.0

Like the InterAct control, the user of this control runs the show by right-clicking over the work area to display a context menu. The user can start a wizard that walks through the steps of creating a chart, or chart his own course, working on whatever component of the chart he chooses at any time, such as chart type, the axis label, chart title, format options for specific data series, and more. Tabbed dialog boxes pop up all over the place, displaying dozens of options. One of the most interesting options the control provides is whether the display metrics are optimized for printing or screen display.         The data that drives the chart can come from one of two sources. Your user can supply the data manually via a grid on one of the chart's property sheets, or the data can be provided programmatically. You could create a grid control somewhere in your Web app where you can either control or help your user supply the data via code. If you're really in the mood, you could give the user the option to specify some other source of data, such as ODBC. Obviously, you'd need to implement this yourself.         When the chart appears as the user wants, it can be saved to a property format, as well as in bitmap and metafile formats. In addition, the user can load existing charts onto the page where the control is placed. The user can also print the chart directly form the work area on the page, as well as specify the printer, page setup options, and the like.         Implementing the First Impression chart control is a no-brainer. You simply add the control to the tool you're using to design your Web page, select the control, and then draw the work area on the page in which the chart will appear. The default chart will appear on the page as soon as it is loaded into a browser. If you do nothing else, the user will have full access to specify data for the chart and format it.         The default chart and its supporting data are not particularly interesting, so you may want to program the data used to drive the chart and its options when the Web page is loaded. Otherwise, visitors to the page where the First Impression control is loaded will be forced to stare at a particularly dull chart. The control comes with a very robust API that lets you not only define how the chart is formatted and what data is charted, but also the behavior of the control's user interface as well. For example, you can specify when certain pop-up dialog boxes appear. Of course, you can build the chart completely from code. The First Impression API comes in the form of an object hierarchy that gives you access to every option exposed in the user interface. A well-documented API reference is provided with the control; in addition, the help file assists with basic charting concepts with the respect to the control, so you don't have to guess about the result of firing an event or method from code. Figure 13 shows the source code for a simple chart-based page.         First Impression is a dynamite control. If your application has any requirement for charting, this control may be the one to use. Crescent Internet ToolPak         A great set of ActiveX components comes with Crescent's Internet ToolPak. In one box you get controls to implement HTTP, FTP, remote access, TCP/IP, telnet, UUEncode/Decode, mail send and receive, and MIME functionality. It's a safe bet that a user will have access to this functionality either directly from their browser or from some other controls. But implementing these controls on your Web page can give you control over how the user accesses the Internet resources from your page, enabling you to build a completely customized and almost foolproof solution. Imagine providing a full suite of Internet tools directly from one page. Pretty cool.         The value of the Internet ToolPak is that the controls enable the programmer to build Internet applications without requiring a detailed understanding of Internet protocols or the Internet in general. Just add the control to a page, meticulously duplicate the code and properties shown in the examples provided in the documentation, customize the application without straying too far from the example, and you're all set. One of the controls that you can get running extremely quickly is the CIPOP3 control, which implements POP3 (Post Office Protocol). Basically, this protocol defines how users can retrieve messages from an electronic post office across the Internet. A complementary Toolpak control, CISMTP, is used to create applications that send messages to an Internet mailbox server and to interrogate mail lists. I'll just take a look at the CIPOP3 control.         With just a handful of properties, you can retrieve messages waiting for you in an Internet mailbox. With a mailbox host name, username, password, and connection to the Internet, the control returns to you the number of messages waiting and details about every message it finds.         Figure 14 shows how you can check your mail from a Web page. Here's how the code works. A few obvious properties you must define for the control are the host server name, a password, and a username. You can define these properties on the property sheet for the control at design time or in code at run time. I've done a combination of both (the host server name is defined on the property sheet). To connect to the server, you call the ConnectToPOPServer method for the control, which returns a 0 on success or something else on failure. You next pass in the user name and password by calling the USER and PASS methods for the control. You've already set the value of these properties, so all you do is call those methods with no parameters. If neither of those methods return errors, you can start to work with the messages in your mailbox if you have any.         The STAT method is called if you are still in the function after passing in the password. When called, the STAT method updates the TotalMessages property.         You can work with individual messages by assigning each message a unique ID of your choice. After assigning a value to the MessageNumber property, you call the RETR method. This method assigns the MessageNumber property to the next message in the mailbox, and it populates the component's properties with a number of properties for the message, such as Sender, Messagebody, and so on. You get the picture. You must repeat the steps of assigning a MessageNumber and calling the RETR method for as many messages as are reported to be in your mailbox. Figure 13 shows how the CIPOP3 control is coded into a page.         The other controls in the Internet ToolPak are just as easy to use. With minimal coding, you can add any Internet feature you want to a Web app. In addition to the standard HTTP, FTP, and newsreader capabilities, your user probably would appreciate UUEncode/Decode, as well as MIME tools, built right into a page where they might be used. FarPoint Technologies Spread 2.5         This will make you just about forget about any other spreadsheet control (unless, of course, you have already purchased one). The FarPoint Technologies Spread 2.5 control is an excellent choice for implementing professional, high-end spreadsheet functionality on a Web page. Let's say that you don't really want or need the overhead or complexity of a spreadsheet—no problem. You can customize the spreadsheet to operate as a simple table control. If your application requires the user to enter or analyze data in rows and columns, this control is for you. But you can also scale its implementation down to, say, build one of those mortgage calculators that appears on one of every three Web sites. This control is definitely worth consideration for presenting almost any amount of columnar data.         The value of the control comes from the huge number of runtime properties and behaviors you can specify for it, as well as the ease of use in specifying these options. Perhaps the most impressive aspect of this control is found in the Spread Designer module. Depending on the tool you use to integrate the Spread control on a Web page, you can enter the nirvana of design modes by choosing Spread Designer from Spread's context menu. This brings you to a mode where it appears that you are using the spreadsheet control as a user, but instead you are specifying runtime properties (see Figure 15). By making choices from menus and oodles of dialog boxes, you can specify dozens of options for the spreadsheet control that will determine how the control looks and behaves when a real user has their hands and cursors on it.

Figure 15: Spread 2.5 from FarPoint Technologies

Another nicety of Spread Designer is its mode selection. What's one of the biggest nuisances when designing Web pages? Testing them? Ding! Correct. This is not the case with Spread Designer. Just choose Run-Time Mode from the menu, and your spreadsheet will run as it will when a user sees it on a Web page (or close to it).         The range of options you can specify for the control is staggering. Want to limit the number of rows and columns? No problem. Want to lock certain cells? No problem. Want to implement custom functions? You got it. How about defining movement of the cursor and block selection behavior? No problem! Colors, fonts, row and column headings and gridlines? You've got to be kidding. Want a mansion and a yacht? Well…         Another nifty feature of the control is the type assignment you can make to individual cells. A cell can be formatted to display a dropdown list that shrinks and grows as you change the height and width of the column and row, a button (choose from two state or push button), a checkbox, plain, boring data, or about seven other types.         Spread 2.5 leaves little to risk when your user starts running the control because you have the capability to completely customize and control what they can and can't do. The Spread Designer makes it simple and extremely intuitive to specify options for the control.        As much as you can customize the runtime behavior control of the control, if you want to give your user the capability to do anything with the data they've entered, such as saving it to a file, you'll have to program this yourself. Again, no problem. The control's API is solid, and any behavior or property that could not be designed in advance, or that you chose not to design in advance, can easily be handled in code. In addition, any of the properties or behaviors specified from Spread Designer, naturally, can be specified and modified in scripting code. The API gives you all the capabilities to finish the implementation of the control, such as a provision for saving to a proprietary file, binding the spreadsheet to a data source, copying and pasting, and more. The on-line documentation supplied with the control also is excellent.         There are of course hundreds of other great ActiveX components available for you to exploit—I've only touched upon a few here that I've found particularly useful. With the free-for-the-downloading beta version of the Visual Basic 5.0 Control Creation Edition that Microsoft recently made available (check out msdn.microsoft.com), the task of actually creating an ActiveX component has become much less difficult. Expect to see a bumper crop of new, innovative components in the coming weeks. See the sidebar "NCompass Labs". For further information contact: DameWare Development 1024 Live Oak Loop Mandeville, LA 70448 504-626-7545 http://atlantis.ni-inc.com/~dameware FarPoint Technologies, Inc. 133 Southcenter Court, Suite 1000 Morrisville, NC 27560 919-460-4551 http://www.fpoint.com MicroHelp, Inc. 4211 JVL Industrial Park Drive Marietta, GA 30066 800-922-3383 770-516-0899 http://www.microhelp.com Microsoft Corp. One Microsoft Way Redmond, WA 98052 206-882-8080 http://www.microsoft.com Progress Software Corporation(Crescent) 14 Oak Park Bedford, MA 01730 617-280-4000 http://www.progress.com ProtoView 2540 Route 130 Cranbury, NJ 08512 800-231-8588 http://www.protoview.com Visual Components, Inc. 15721 College Blvd. Lenexa, KS 66219 913-599-6500 http://www.visualcomp.com From the January 1997 issue of Microsoft Interactive Developer.