The sample Web site must reside on a FrontPage-enabled Web server capable of in C#.NET

Drawer QR Code 2d barcode in C#.NET The sample Web site must reside on a FrontPage-enabled Web server capable of

For more information about using server-based Web sites, refer to Using Server-Based Web Sites, on page 146.

For more information about marking Web server folders as executable, refer to Reviewing Folder Settings, on page 1144, or Configuring Home Directory Settings, in Appendix O.

to load the slider.htm page. Loading the slider.htm page directly from disk won t work because the browser will then try to load sliderqty.asp from disk as well. And that won t work because:

of the software resources present on the Web server would be available. Of course, a real Web page of this type would contain more than one field. The ASP page or other process on the Web server would perform more complex processing than simply 798

Using ActiveX Controls and Java Applets echoing values back to the Web visitor. Nevertheless, this example illustrates the use of ActiveX controls to enhance the Web visitor s experience. This Web page, by the way, works perfectly well in Netscape Navigator. For proof, inspect Figure 32-11. Netscape ignores the slider object, and the script code bypasses any references to Slider1 when Netscape is the browser. The page therefore functions as a perfectly normal HTML form.

Figure 32-11. Netscape Navigator ignores ActiveX controls in Web pages. However, with suitable precautions, the page can still be functional.

Figure 32-12 shows FrontPage displaying another ActiveX control: a Calendar control. When the Web visitor uses the list boxes at the upper right to select a month and a year, the grid of days changes to reflect the proper dates. Clicking any day makes the month, day, and year available to scripts and other elements in the Web page. The Calendar control is an attractive way to collect dates from Web visitors, but as with the Slider control, clicking an HTML form s Submit button doesn t transmit the Calendar con trol s values to the Web server. To overcome this limitation, this Web page s Submit button is actually a push button that runs a small script. The script copies the Calendar control s cur rently selected year, month, and day values into three hidden form fields and then submits the form. This transmits the three copied values to the Web server for processing.

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Figure 32-12.

You can create most of the HTML code for the push button by choosing Form from the Insert menu and then choosing Push Button. The button s name isn t important, but if you want it to be btnSub, display the button s Properties dialog box and change the Name field. The code is as follows:

Notice that this button isn t a Submit button. Clicking it doesn t submit the form. Instead, the onClick attribute runs a function named subForm whenever the visitor clicks the button. You must add this attribute to the button s HTML code manually, in Code view. Tip If you select a button (or any other page element) in Design view, it will still be selected when you switch to Code view. The following information will help you understand the code for the subForm function:

The Calendar control s name is cal01. Whenever the Web visitor selects a date, the Calendar control s month, day, and year

The HTML form s name is form1. The HTML form contains three hidden form fields named qmon, qday, and qyr. These

fields have no visual presence on the Web page, but the browser nevertheless submits their values when it submits the form.

Using ActiveX Controls and Java Applets To view the definition of these hidden form fields:

Figure 32-13. The HTML that creates the Submit button on this Web page has three hidden form fields.

When the Web visitor clicks Submit, the subForm function first checks to see whether cal01.day the Calendar control s day of the month value is greater than zero. If so, it copies the cal01.month, cal01.day, and cal01.year values to the hidden form fields qmon, qday, and qyr and then submits the form. Otherwise, it displays a message to the Web visitor and then exits. The following is the actual code for this function:

function subForm() { if (cal01.day > 0) { form1.qmon.value = cal01.month; form1.qday.value = cal01.day; form1.qyr.value = cal01.year; document.form1.submit(); }else{ alert("You must select a date!"); return; } }

To view this page in a browser, open the sample Web site, select ch32/bdaysel.htm, and then choose Preview In Browser from the File menu. Figure 32-14 shows the results. 801