Page Content Data Access in VS .NET

Printing QR-Code in VS .NET Page Content Data Access

Instead of sending a complete result set to the user, only send the data record that the user is interested in. Only bind the required controls. Test adaptive controls with several devices, including devices that display a few lines. Present the user with default values whenever possible. In many applications, better performance may be obtained by turning off ViewState, because this reduces the amount of data that is being transferred to a slow mobile device. Turning off ViewState may require the server to rebuild the data each time the user posts back to the server.

Whenever possible, cache data access results to keep from retriev ing data each time the user accesses the server. It is much easier to share data between forms on a page than it is to share data between pages. However, there is a point where performance suffers. Look for places where it is easy to pass a few items to a new page.

Many mobile devices do not support cookies, so it is important to use cookieless sessions. Use Microsoft SQL Server to store state in a Web farm envi

A hyperlink can be created to a form by using the #form3 syntax. If the page has a user control called myControl, which has forms, a hyperlink can be created using the #myControl:form2 syntax.

This use of images should be kept to a minimum due to the low bandwidth and screen resolution that is available on most mobile devices. Some mobile devices may not support images, while others may not support the image type that is being supplied, such as when a .gif file is used on a mobile device that only supports .wbmp files. Be sure to assign a value to the AlternateText property of all graphics.

1. What is a primary difference between the standard validator controls and the mobile validator controls 2. What can you do to ensure that session state is maintained when mobile devices that don t accept cookies are accessing your mobile Web site

1. The mobile validation controls don t provide client-side validation. 2. You should enable cookieless sessions in the Web.config file.

In this lab, you create a mobile Web site application. This application demonstrates the use of mobile controls to access and display data on a cell phone or browser. This application presents the user with the option of searching the products by name, product ID, or by drilling down through the categories to get to the products.

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In this exercise, you create the mobile Web site and add the controls. 1. Open Visual Studio 2005 and create a new Web site called WorkingWithMo bileWebApplications using your preferred programming language. The new Web site will be created and a standard Web page called Default.aspx is displayed. 2. Delete the Default.aspx Web page. 3. Add a mobile Web form to the Web site, called Default.aspx, which replaces the Default.aspx page that you deleted in the previous step. 4. Switch to Design View, select the mobile form, and set its ID to frmMainMenu and its Title to Select a Search Method. 5. Add another mobile Form control to the page. Set this form s ID to frmSearchName and its Title to Enter Name. 6. Add another mobile Form control to the page. Set this form s ID to frmSearchId and its Title to Enter ID. 7. Add another mobile Form control to the page. Set this form s ID to frmSearchCategory and its Title to Select a Category. 8. Add another mobile Form control to the page. Set this form s ID to frmResult and its Title to Search Result. 9. Add a mobile List control to the frmMainMenu and set the ID to lstMainMenu. Add the following to the Items collection of lstMainMenu: By Name (value=1), By ID (value=2), and By Category (value=3). 10. Add a mobile Label control to frmSearchName and set its ID to lblSearchName and its Text to Enter Name. 11. Add a mobile TextBox control to frmSearchName and set its ID to txtSearchName. 12. Add a mobile Command control to frmSearchName and set its ID to cmdSearchName and its Text to Search. 13. Add a mobile Label control to frmSearchId and set its ID to lblSearchId and its Text to Enter ID. 14. Add a mobile TextBox control to frmSearchId and set its ID to txtSearchId. 15. Add a mobile Command control to frmSearchId and set its ID to cmdSearchId and its Text to Search. 16. Add a List control to frmSearchCategory and set its ID to lstCategories.