Webmaster's Guide to the Wireless Internet part 20. The Webmaster’s Guide to the Wireless Internet provides the Wireless Webmaster with all of the tools necessary to build the next generation Internet. Packed with the essential information they need to design, develop, and secure robust, e-commerce enabled wireless Web sites. This book is written for advanced Webmasters who are experienced with conventional Web site design and are now faced with the challenge of creating sites that fit on the display of a Web enabled phone or PDA | 162 Chapter 4 Enhancing Client-Side Functionality with WMLScript Using WMLScript and Microsoft Active Server Pages ASP Case Study We have seen how WMLScript can be used to perform client-side validation and to complement WML applications that run on a WAP device. One particular application that is very popular is a currency converter. However the conventional currency converter usually hardcodes the exchange rate in the WMLScript program. Once the WMLScript is downloaded onto the device it is cached and any changes to the currency conversion rate would not be reflected in the application. In this case study we will illustrate how you can use ASP to create a truly dynamic WMLScript program using the currency converter application as a case study. Our currency converter is able to reflect the daily changes in the exchange rates. Designing the Application A currency converter application often is used to illustrate the use ofWMLScript. For this example we will use the provided by Openwave. Figure and Figure illustrate the desired outcome of our application. Figure Selecting the USD Option to Convert from and Keying the Amount to Convert Figure Selecting the SIN Option to Convert to and Viewing the Result of the Conversion Enhancing Client-Side Functionality with WMLScript Chapter 4 163 The user simply chooses the currency to convert from keys in the amount to be converted and selects the target currency. The converted currency would then be displayed. Creating the Database Our application makes use of a database containing a single table named database table can be seen in Figure . Figure Our Database Contains One Table Named Conversion This table simply contains the exchange rate of exchange rate is tagged to a fixed currency the Singapore dollar in this case. For example 1 USD US Dollar SIN Singapore Dollar 1 RM Malaysian Ringgit SIN Converting from one currency to .
